Https://github.com/curl/curl: Exposure of Sensitive Information to an Unauthorized Actor (CVE-2021-22898)
Published Last modified Sources: BSI, Debian, OSV, CVE.org
What is affected, what to do
curl 7.7 through 7.76.1 suffers from an information disclosure when the `-t` command line option, known as `CURLOPT_TELNETOPTIONS` in libcurl, is used to send variable=content pairs to TELNET servers. Due to a flaw in the option parser for sending NEW_ENV variables, libcurl could be made to pass on uninitialized data from a stack based buffer to the server, resulting in potentially revealing sensitive internal information to the server using a clear-text network protocol.
Update essbase to version 11.1.2.4.047, mysql_server to version 8.0.25, sinec_infrastructure_network_services to version 1.0.1.1.
- Affected
- Https://github.com/curl/curl
eq 7.7 through 7.76.1..7.7 through 7.76.1
- Https://github.com/curl/curl
Not sure whether and how you are affected? Ask a question about this vulnerability
Metrics
3.1
Priority
XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.
Source: NVD, CVSS v3
3.1
CVSS v3
Severity Low on the scale from 0 to 10.
Source: BSI, Debian, OSV, CVE.org
4.5 %
EPSS score
Moderate — model estimates 1-10% exploitation likelihood.
Source: FIRST EPSS, percentile 91.5
Show all metrics
- Severity
- Low
Priority (0–325)
The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?
Read in glossary- 82.46 Methodology
Exploit maturity
An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.
Read in glossary- no public PoC known
XIEM Effective CVSS
XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.
Read in glossary- 3.1 Methodology
CVSS v3
CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.
Read in glossary- 3.1
EPSS score
The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.
Read in glossary- 4.5 %
- Moderate — model estimates 1-10% exploitation likelihood.
EPSS percentile
The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.
Read in glossary- 91.5
- Critical — this CVE ranks in the top fifth of all CVEs scored today (rank ≥ 80%).
KEV status
The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.
Read in glossary- —
- Published
- CISA assessment (SSVC)
- Exploitation: proof of concept · not automatable · Technical impact: partial
- Source: CISA Vulnrichment, as of 28 March 2024
CWE
CWE is a catalogue of typical weakness types in software and hardware — such as flawed input validation, unsafe memory handling or poor authentication. Where a CVE names a concrete vulnerability in a concrete product, a CWE describes the underlying class of defect.
Read in glossary- CWE-200
Detection rules
No NEOSEC detection rule is available for this vulnerability yet.
Classification under NIS2 and CRA
Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.
NIS2
NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.
Read in glossary- Handle the vulnerability in regular vulnerability handling under Art. 21(2)(e) NIS2.
CRA
The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.
Read in glossary- From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
ISO/IEC 27001
ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.
Read in glossary- Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.
Description
curl 7.7 through 7.76.1 suffers from an information disclosure when the `-t` command line option, known as `CURLOPT_TELNETOPTIONS` in libcurl, is used to send variable=content pairs to TELNET servers. Due to a flaw in the option parser for sending NEW_ENV variables, libcurl could be made to pass on uninitialized data from a stack based buffer to the server, resulting in potentially revealing sensitive internal information to the server using a clear-text network protocol.
Source: BSI CSAF, BSI WID Portal, Debian Security Advisories, OSV (Open Source Vulnerabilities), NVD (NIST), cvelistv5
Affected products
The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.
| Affected versions | Fixed in | ||
|---|---|---|---|
| — | https://github.com/curl/curl |
|
|
| haxx | curl |
|
|
| oracle | communications_cloud_native_core_binding_support_function |
|
|
| oracle | communications_cloud_native_core_network_function_cloud_native_environment |
|
|
| oracle | communications_cloud_native_core_network_repository_function |
|
|
| oracle | communications_cloud_native_core_network_slice_selection_function |
|
|
| oracle | communications_cloud_native_core_service_communication_proxy |
|
|
| oracle | essbase |
|
|
| oracle | mysql_server |
|
|
| siemens | sinec_infrastructure_network_services |
|
|
| splunk | universal_forwarder |
|
|
Vendors and products
- Debian Curl
- Debian Debian Linux
- Fedora Project Infrastructure Fedora
- Google Haxx Curl
- Oracle Communications Cloud Native Core Binding Support Function
- Oracle Communications Cloud Native Core Network Function Cloud Native Environment
- Oracle Communications Cloud Native Core Network Repository Function
- Oracle Communications Cloud Native Core Network Slice Selection Function
- Oracle Communications Cloud Native Core Service Communication Proxy
- Oracle Oracle Essbase
- Oracle Oracle MySQL Server
- Siemens Sinec Infrastructure Network Services
Affected operating systems
| Linux | debian | curl | bullseye |
| Linux | debian | debian_linux | 9.0 |
| Other | fedoraproject | fedora | 33 |
| Other | fedoraproject | fedora | 34 |
Weakness classes (CWE)
CWE-200Exposure of Sensitive Information to an Unauthorized Actor
Class
The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.
Entry at MITRE CWE-200
References & sources
- hackerone.comreports/1176461x_refsource_MISC
- curl.sedocs/CVE-2021-22898.htmlx_refsource_MISC
- github.comcurl/curl/commit/39ce47f219b09c380b81f89fe54ac586c8db6bdex_refsource_MISC
- lists.apache.org[guacamole-issues] 20210618 [jira] [Created] (GUACAMOLE-1368) Latest docker image fails security scans.Mailing list, x_refsource_MLIST
- oracle.comsecurity-alerts/cpujul2021.htmlx_refsource_MISC
- openwall.com[oss-security] 20210721 [SECURITY ADVISORY] curl: TELNET stack contents disclosure againMailing list, x_refsource_MLIST
- lists.fedoraproject.orgFEDORA-2021-83fdddca0fVendor advisory, x_refsource_FEDORA
- lists.fedoraproject.orgFEDORA-2021-5d21b90a30Vendor advisory, x_refsource_FEDORA
- lists.debian.org[debian-lts-announce] 20210813 [SECURITY] [DLA 2734-1] curl security updateMailing list, x_refsource_MLIST
- oracle.comsecurity-alerts/cpujan2022.htmlx_refsource_MISC
- oracle.comsecurity-alerts/cpuapr2022.htmlx_refsource_MISC
- Siemens ProductCERTproductcert/pdf/ssa-389290.pdfx_refsource_CONFIRM
- debian.orgDSA-5197Vendor advisory, x_refsource_DEBIAN
- lists.debian.org[debian-lts-announce] 20220828 [SECURITY] [DLA 3085-1] curl security updateMailing list, x_refsource_MLIST
- Siemens ProductCERTproductcert/html/ssa-398330.html
Changes to this CVE
Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).
Record modifiedHackerOne
Show 42 original changes
Individual changes of this event as published by NVD Type Action Before After Reference added —http://www.openwall.com/lists/oss-security/2021/07/21/4Reference added —https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdfReference added —https://curl.se/docs/CVE-2021-22898.htmlReference added —https://github.com/curl/curl/commit/39ce47f219b09c380b81f89fe54ac586c8db6bdeReference added —https://hackerone.com/reports/1176461Reference added —https://lists.apache.org/thread.html/rc713534b10f9daeee2e0990239fa407e2118e4aa9e88a7041177497c%40%3Cissues.guacamole.apache.org%3EReference added —https://lists.debian.org/debian-lts-announce/2021/08/msg00017.htmlReference added —https://lists.debian.org/debian-lts-announce/2022/08/msg00017.htmlReference added —https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FRUCW2UVNYUDZF72DQLFQR4PJEC6CF7V/Reference added —https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/POOC3UV7V6L4CJ5KA2PTWTNUV5Y72T3Q/Reference added —https://www.debian.org/security/2022/dsa-5197Reference added —https://www.oracle.com//security-alerts/cpujul2021.htmlReference added —https://www.oracle.com/security-alerts/cpuapr2022.htmlReference added —https://www.oracle.com/security-alerts/cpujan2022.htmlReference removed http://www.openwall.com/lists/oss-security/2021/07/21/4—Reference removed https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf—Reference removed https://curl.se/docs/CVE-2021-22898.html—Reference removed https://github.com/curl/curl/commit/39ce47f219b09c380b81f89fe54ac586c8db6bde—Reference removed https://hackerone.com/reports/1176461—Reference removed https://lists.apache.org/thread.html/rc713534b10f9daeee2e0990239fa407e2118e4aa9e88a7041177497c%40%3Cissues.guacamole.apache.org%3E—Reference removed https://lists.debian.org/debian-lts-announce/2021/08/msg00017.html—Reference removed https://lists.debian.org/debian-lts-announce/2022/08/msg00017.html—Reference removed https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FRUCW2UVNYUDZF72DQLFQR4PJEC6CF7V/—Reference removed https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/POOC3UV7V6L4CJ5KA2PTWTNUV5Y72T3Q/—Reference removed https://www.debian.org/security/2022/dsa-5197—Reference removed https://www.oracle.com//security-alerts/cpujul2021.html—Reference removed https://www.oracle.com/security-alerts/cpuapr2022.html—Reference removed https://www.oracle.com/security-alerts/cpujan2022.html—Reference type removed http://www.openwall.com/lists/oss-security/2021/07/21/4 Types: Mailing List, Patch, Third Party Advisory—Reference type removed https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf Types: Patch, Third Party Advisory—Reference type removed https://curl.se/docs/CVE-2021-22898.html Types: Exploit, Patch, Vendor Advisory—Reference type removed https://github.com/curl/curl/commit/39ce47f219b09c380b81f89fe54ac586c8db6bde Types: Patch, Third Party Advisory—Reference type removed https://hackerone.com/reports/1176461 Types: Exploit, Issue Tracking, Patch, Third Party Advisory—Reference type removed https://lists.apache.org/thread.html/rc713534b10f9daeee2e0990239fa407e2118e4aa9e88a7041177497c%40%3Cissues.guacamole.apache.org%3E Types: Mailing List, Third Party Advisory—Reference type removed https://lists.debian.org/debian-lts-announce/2021/08/msg00017.html Types: Mailing List, Third Party Advisory—Reference type removed https://lists.debian.org/debian-lts-announce/2022/08/msg00017.html Types: Third Party Advisory—Reference type removed https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FRUCW2UVNYUDZF72DQLFQR4PJEC6CF7V/ Types: Mailing List, Third Party Advisory—Reference type removed https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/POOC3UV7V6L4CJ5KA2PTWTNUV5Y72T3Q/ Types: Mailing List, Third Party Advisory—Reference type removed https://www.debian.org/security/2022/dsa-5197 Types: Third Party Advisory—Reference type removed https://www.oracle.com//security-alerts/cpujul2021.html Types: Patch, Third Party Advisory—Reference type removed https://www.oracle.com/security-alerts/cpuapr2022.html Types: Patch, Third Party Advisory—Reference type removed https://www.oracle.com/security-alerts/cpujan2022.html Types: Patch, Third Party Advisory—Source identifier: support@hackerone.com
Record modifiedCVE Program
Show 42 original changes
Individual changes of this event as published by NVD Type Action Before After Reference added —http://www.openwall.com/lists/oss-security/2021/07/21/4Reference added —https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdfReference added —https://curl.se/docs/CVE-2021-22898.htmlReference added —https://github.com/curl/curl/commit/39ce47f219b09c380b81f89fe54ac586c8db6bdeReference added —https://hackerone.com/reports/1176461Reference added —https://lists.apache.org/thread.html/rc713534b10f9daeee2e0990239fa407e2118e4aa9e88a7041177497c%40%3Cissues.guacamole.apache.org%3EReference added —https://lists.debian.org/debian-lts-announce/2021/08/msg00017.htmlReference added —https://lists.debian.org/debian-lts-announce/2022/08/msg00017.htmlReference added —https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FRUCW2UVNYUDZF72DQLFQR4PJEC6CF7V/Reference added —https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/POOC3UV7V6L4CJ5KA2PTWTNUV5Y72T3Q/Reference added —https://www.debian.org/security/2022/dsa-5197Reference added —https://www.oracle.com//security-alerts/cpujul2021.htmlReference added —https://www.oracle.com/security-alerts/cpuapr2022.htmlReference added —https://www.oracle.com/security-alerts/cpujan2022.htmlReference removed http://www.openwall.com/lists/oss-security/2021/07/21/4—Reference removed https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf—Reference removed https://curl.se/docs/CVE-2021-22898.html—Reference removed https://github.com/curl/curl/commit/39ce47f219b09c380b81f89fe54ac586c8db6bde—Reference removed https://hackerone.com/reports/1176461—Reference removed https://lists.apache.org/thread.html/rc713534b10f9daeee2e0990239fa407e2118e4aa9e88a7041177497c%40%3Cissues.guacamole.apache.org%3E—Reference removed https://lists.debian.org/debian-lts-announce/2021/08/msg00017.html—Reference removed https://lists.debian.org/debian-lts-announce/2022/08/msg00017.html—Reference removed https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FRUCW2UVNYUDZF72DQLFQR4PJEC6CF7V/—Reference removed https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/POOC3UV7V6L4CJ5KA2PTWTNUV5Y72T3Q/—Reference removed https://www.debian.org/security/2022/dsa-5197—Reference removed https://www.oracle.com//security-alerts/cpujul2021.html—Reference removed https://www.oracle.com/security-alerts/cpuapr2022.html—Reference removed https://www.oracle.com/security-alerts/cpujan2022.html—Reference type removed http://www.openwall.com/lists/oss-security/2021/07/21/4 Types: Mailing List, Patch, Third Party Advisory—Reference type removed https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf Types: Patch, Third Party Advisory—Reference type removed https://curl.se/docs/CVE-2021-22898.html Types: Exploit, Patch, Vendor Advisory—Reference type removed https://github.com/curl/curl/commit/39ce47f219b09c380b81f89fe54ac586c8db6bde Types: Patch, Third Party Advisory—Reference type removed https://hackerone.com/reports/1176461 Types: Exploit, Issue Tracking, Patch, Third Party Advisory—Reference type removed https://lists.apache.org/thread.html/rc713534b10f9daeee2e0990239fa407e2118e4aa9e88a7041177497c%40%3Cissues.guacamole.apache.org%3E Types: Mailing List, Third Party Advisory—Reference type removed https://lists.debian.org/debian-lts-announce/2021/08/msg00017.html Types: Mailing List, Third Party Advisory—Reference type removed https://lists.debian.org/debian-lts-announce/2022/08/msg00017.html Types: Third Party Advisory—Reference type removed https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FRUCW2UVNYUDZF72DQLFQR4PJEC6CF7V/ Types: Mailing List, Third Party Advisory—Reference type removed https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/POOC3UV7V6L4CJ5KA2PTWTNUV5Y72T3Q/ Types: Mailing List, Third Party Advisory—Reference type removed https://www.debian.org/security/2022/dsa-5197 Types: Third Party Advisory—Reference type removed https://www.oracle.com//security-alerts/cpujul2021.html Types: Patch, Third Party Advisory—Reference type removed https://www.oracle.com/security-alerts/cpuapr2022.html Types: Patch, Third Party Advisory—Reference type removed https://www.oracle.com/security-alerts/cpujan2022.html Types: Patch, Third Party Advisory—Source identifier: af854a3a-2127-422b-91ae-364da2661108
Record modifiedSiemens ADP
Show 2 original changes
Individual changes of this event as published by NVD Type Action Before After Affected versions (publisher) added —New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2021/22xxx/CVE-2021-22898.json">CVE-2021-22898</a>Reference added —https://cert-portal.siemens.com/productcert/html/ssa-398330.htmlSource identifier: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
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<a href="https://intel.neosec.eu/en/cve/CVE-2021-22898"><img src="https://intel.neosec.eu/badge/cve/CVE-2021-22898.svg?lang=en" alt="CVE-2021-22898 – NEOSEC Intel" height="20"></a>