Out-of-bounds read in HTTP client no_proxy handling (CVE-2025-9232)
Published Last modified Sources: Siemens ProductCERT, Red Hat, Ubuntu, BSI, CVE.org, Debian, Msrc Update Guide, SUSE, EUVD
What is affected, what to do
Issue summary: An application using the OpenSSL HTTP client API functions may trigger an out-of-bounds read if the 'no_proxy' environment variable is set and the host portion of the authority component of the HTTP URL is an IPv6 address. Impact summary: An out-of-bounds read can trigger a crash which leads to Denial of Service for an application.
Update OpenSSL to version 3.5.4, OpenSSL to version 3.4.3, OpenSSL to version 3.3.5.
- Affected
- OpenSSL
lt 3.5.0..3.5.4 - OpenSSL
lt 3.4.0..3.4.3 - OpenSSL
lt 3.3.3..3.3.5 - OpenSSL
lt 3.2.4..3.2.6 - OpenSSL
lt 3.0.16..3.0.18
- OpenSSL
- Fixed in
- OpenSSL
3.5.4 - OpenSSL
3.4.3 - OpenSSL
3.3.5 - OpenSSL
3.2.6 - OpenSSL
3.0.18
- OpenSSL
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Metrics
5.9
Priority
XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.
Source: NVD, CVSS v3
5.9
CVSS v3
Severity Medium on the scale from 0 to 10.
Source: Siemens ProductCERT, Red Hat, Ubuntu, BSI, CVE.org, Debian, Msrc Update Guide, SUSE, EUVD
2.2 %
EPSS score
Moderate — model estimates 1-10% exploitation likelihood.
Source: FIRST EPSS, percentile 82.8
Show all metrics
- Severity
- Medium
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- 95.26 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- 5.9 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- 5.9
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- 2.2 %
- 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- 82.8
- 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: none known · not automatable · Technical impact: partial
- Source: CISA Vulnrichment, as of 30 September 2025
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-125
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
Issue summary: An application using the OpenSSL HTTP client API functions may trigger an out-of-bounds read if the 'no_proxy' environment variable is set and the host portion of the authority component of the HTTP URL is an IPv6 address. Impact summary: An out-of-bounds read can trigger a crash which leads to Denial of Service for an application. The OpenSSL HTTP client API functions can be used directly by applications but they are also used by the OCSP client functions and CMP (Certificate Management Protocol) client implementation in OpenSSL. However the URLs used by these implementations are unlikely to be controlled by an attacker. In this vulnerable code the out of bounds read can only trigger a crash. Furthermore the vulnerability requires an attacker-controlled URL to be passed from an application to the OpenSSL function and the user has to have a 'no_proxy' environment variable set. For the aforementioned reasons the issue was assessed as Low severity. The vulnerable code was introduced in the following patch releases: 3.0.16, 3.1.8, 3.2.4, 3.3.3, 3.4.0 and 3.5.0. The FIPS modules in 3.5, 3.4, 3.3, 3.2, 3.1 and 3.0 are not affected by this issue, as the HTTP client implementation is outside the OpenSSL FIPS module boundary.
Source: siemens_advisory, redhat_csaf, Ubuntu Security Notices, BSI WID Portal, BSI CSAF, NVD (NIST), Debian Security Advisories, cvelistv5, Microsoft Security Update Guide, suse_csaf, CVE.org (MITRE), ENISA EUVD
Affected products
The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.
| Affected versions | Fixed in | ||
|---|---|---|---|
| OpenSSL | OpenSSL |
|
|
| openssl | openssl |
|
|
| siemens | sidis_prime |
|
|
| Dell | Secure Connect Gateway Appliance |
|
|
| IBM | AIX |
|
|
| IBM | DevOps Code ClearCase |
|
|
| IBM | MQ |
|
|
| IBM | TXSeries |
|
|
| IBM | VIOS |
|
|
| IGEL | OS |
|
|
| Meinberg | LANTIME |
|
|
| Open Source | OpenSSL |
|
|
| Red Hat | OpenShift Container Platform |
|
|
| SolarWinds | Platform |
|
|
| Splunk | Splunk Enterprise |
|
|
| Xerox | FreeFlow Print Server |
|
|
Vendors and products
Affected operating systems
| Linux | debian | openssl | bookworm |
| Linux | debian | openssl | trixie |
| Linux | ubuntu | openssl | bionic |
| Linux | ubuntu | openssl | focal |
| Linux | ubuntu | openssl | jammy |
| Linux | ubuntu | openssl | noble |
| Linux | ubuntu | openssl | plucky |
| Linux | ubuntu | openssl | trusty |
| Linux | ubuntu | openssl | xenial |
| Linux | ubuntu | openssl1.0 | bionic |
| Other | siemens | ruggedcom_rst2428p_firmware | — |
| Other | siemens | sidis_secured_smartplug_firmware | — |
| Other | siemens | simatic_cn_4100_firmware | — |
| Other | siemens | simatic_s7-1500_cpu_1518-4_pn\/dp_mfp_firmware | 3.1.5 |
| Other | siemens | simatic_s7-1500_cpu_1518f-4_pn\/dp_mfp_firmware | 3.1.5 |
| Other | siemens | sinec_os | — |
| Other | siemens | siplus_s7-1500_cpu_1518-4_pn\/dp_mfp_firmware | 3.1.5 |
Weakness classes (CWE)
CWE-125Out-of-bounds Read
Base
The product reads data past the end, or before the beginning, of the intended buffer.
Entry at MITRE CWE-125
References & sources
- openssl-library.orgOpenSSL AdvisoryVendor advisory, Vendor advisory
- github.com3.5.4 git commitPatch, Patch
- github.com3.4.3 git commitPatch, Patch
- github.com3.3.5 git commitPatch, Patch
- github.com3.2.6 git commitPatch, Patch
- github.com3.0.18 git commitPatch, Patch
- openwall.comlists/oss-security/2025/09/30/5Mailing list, Third-party advisory
- Siemens ProductCERTproductcert/html/ssa-082556.htmlThird-party advisory
- Siemens ProductCERTproductcert/html/ssa-089022.htmlThird-party advisory
- Siemens ProductCERTproductcert/html/ssa-485750.htmlThird-party advisory
- Siemens ProductCERTproductcert/html/ssa-032379.htmlThird-party advisory
- Siemens ProductCERTproductcert/html/ssa-253495.htmlThird-party advisory
- Siemens ProductCERTproductcert/html/ssa-585531.htmlThird-party advisory
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).
Initial analysis by NVDNVD
Newly listed as affected:- OpenSSL (1.0.2 – before 1.0.2zm; 1.1.1 – before 1.1.1zd; 3.0.0 – before 3.0.18; 3.2.0 – before 3.2.6; 3.3.0 – before 3.3.5; 3.4.0 – before 3.4.3; 3.5.0 – before 3.5.4)
- Siemens SIMATIC CN 4100 Firmware (before 5.0)
- Siemens simatic s7-1500 cpu 1518-4 pn/dp mfp firmware (3.1.5)
- Siemens simatic s7-1500 cpu 1518f-4 pn/dp mfp firmware (3.1.5)
- Siemens siplus s7-1500 cpu 1518-4 pn/dp mfp firmware (3.1.5)
- Siemens SINEC OS (before 3.3)
- Siemens RUGGEDCOM RST2428P Firmware (before 4.0)
- Siemens Sidis Prime (before 4.0.800)
- Siemens sidis secured smartplug firmware (before 7.26.0310)
New references:- https://github.com/openssl/openssl/commit/2b4ec20e47959170422922eaff25346d362dcb35
- https://github.com/openssl/openssl/commit/654dc11d23468a74fc8ea4672b702dd3feb7be4b
- https://github.com/openssl/openssl/commit/7cf21a30513c9e43c4bc3836c237cf086e194af3
- https://github.com/openssl/openssl/commit/89e790ac431125a4849992858490bed6b225eadf
and 8 more references
Show 22 original changes
Individual changes of this event as published by NVD Type Action Before After Product configuration added —OR *cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* versions from (including) 1.0.2 up to (excluding) 1.0.2zm *cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* versions from (including) 1.1.1 up to (excluding) 1.1.1zd *cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* versions from (including) 3.0.0 up to (excluding) 3.0.18 *cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* versions from (including) 3.2.0 up to (excluding) 3.2.6 *cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* versions from (including) 3.3.0 up to (excluding) 3.3.5 *cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* versions from (including) 3.4.0 up to (excluding) 3.4.3 *cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* versions from (including) 3.5.0 up to (excluding) 3.5.4Product configuration added —AND OR *cpe:2.3:o:siemens:simatic_cn_4100_firmware:*:*:*:*:*:*:*:* versions up to (excluding) 5.0 OR cpe:2.3:h:siemens:simatic_cn_4100:-:*:*:*:*:*:*:*Product configuration added —AND OR *cpe:2.3:o:siemens:simatic_s7-1500_cpu_1518-4_pn/dp_mfp_firmware:3.1.5:*:*:*:*:*:*:* OR cpe:2.3:h:siemens:simatic_s7-1500_cpu_1518-4_pn/dp_mfp:-:*:*:*:*:*:*:*Product configuration added —AND OR *cpe:2.3:o:siemens:simatic_s7-1500_cpu_1518f-4_pn/dp_mfp_firmware:3.1.5:*:*:*:*:*:*:* OR cpe:2.3:h:siemens:simatic_s7-1500_cpu_1518f-4_pn/dp_mfp:-:*:*:*:*:*:*:*Product configuration added —AND OR *cpe:2.3:o:siemens:siplus_s7-1500_cpu_1518-4_pn/dp_mfp_firmware:3.1.5:*:*:*:*:*:*:* OR cpe:2.3:h:siemens:siplus_s7-1500_cpu_1518-4_pn/dp_mfp:-:*:*:*:*:*:*:*Product configuration added —AND OR *cpe:2.3:o:siemens:sinec_os:*:*:*:*:*:*:*:* versions up to (excluding) 3.3 OR cpe:2.3:h:siemens:scalance_xr524-8c:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xr526-8c:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xr528-6m:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xr552-12m:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xc316-8:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xc319-4:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xc324-4:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xc324-4eec:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xc332:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xch328:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xcm324:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xcm328:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xcm332:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xrh334:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xrm334:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xc416-8:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xc419-4:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xc424-4:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xc432:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xr302-32:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xr322-12:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xr326-8:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xr326-8eec:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xr502-32:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xr522-12:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xr524-8wg:-:*:*:*:*:*:*:* cpe:2.3:h:siemens:scalance_xr526-8:-:*:*:*:*:*:*:*Product configuration added —AND OR *cpe:2.3:o:siemens:ruggedcom_rst2428p_firmware:*:*:*:*:*:*:*:* versions up to (excluding) 4.0 OR cpe:2.3:h:siemens:ruggedcom_rst2428p:-:*:*:*:*:*:*:*Product configuration added —OR *cpe:2.3:a:siemens:sidis_prime:*:*:*:*:*:*:*:* versions up to (excluding) 4.0.800Product configuration added —AND OR *cpe:2.3:o:siemens:sidis_secured_smartplug_firmware:*:*:*:*:*:*:*:* versions up to (excluding) 7.26.0310 OR cpe:2.3:h:siemens:sidis_secured_smartplug:-:*:*:*:*:*:*:*Reference type added —OpenSSL Software Foundation: https://github.com/openssl/openssl/commit/2b4ec20e47959170422922eaff25346d362dcb35 Types: PatchReference type added —OpenSSL Software Foundation: https://github.com/openssl/openssl/commit/654dc11d23468a74fc8ea4672b702dd3feb7be4b Types: PatchReference type added —OpenSSL Software Foundation: https://github.com/openssl/openssl/commit/7cf21a30513c9e43c4bc3836c237cf086e194af3 Types: PatchReference type added —OpenSSL Software Foundation: https://github.com/openssl/openssl/commit/89e790ac431125a4849992858490bed6b225eadf Types: PatchReference type added —OpenSSL Software Foundation: https://github.com/openssl/openssl/commit/bbf38c034cdabd0a13330abcc4855c866f53d2e0 Types: PatchReference type added —OpenSSL Software Foundation: https://openssl-library.org/news/secadv/20250930.txt Types: Vendor AdvisoryReference type added —CVE: http://www.openwall.com/lists/oss-security/2025/09/30/5 Types: Mailing List, Third Party AdvisoryReference type added —siemens-SADP: https://cert-portal.siemens.com/productcert/html/ssa-032379.html Types: Third Party AdvisoryReference type added —siemens-SADP: https://cert-portal.siemens.com/productcert/html/ssa-082556.html Types: Third Party AdvisoryReference type added —siemens-SADP: https://cert-portal.siemens.com/productcert/html/ssa-089022.html Types: Third Party AdvisoryReference type added —siemens-SADP: https://cert-portal.siemens.com/productcert/html/ssa-253495.html Types: Third Party AdvisoryReference type added —siemens-SADP: https://cert-portal.siemens.com/productcert/html/ssa-485750.html Types: Third Party AdvisoryReference type added —siemens-SADP: https://cert-portal.siemens.com/productcert/html/ssa-585531.html Types: Third Party AdvisorySource identifier: nvd@nist.gov
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<a href="https://intel.neosec.eu/en/cve/CVE-2025-9232"><img src="https://intel.neosec.eu/badge/cve/CVE-2025-9232.svg?lang=en" alt="CVE-2025-9232 – NEOSEC Intel" height="20"></a>