HighCVE-2026-102994

    URI: Uncontrolled Resource Consumption (CVE-2026-102994)

    Published

    What is affected, what to do

    pypdf is a free and open-source pure-python PDF library. Prior to 6.18.0, a crafted PDF containing indirect-object identifiers or generation-number tokens that continue for a long time without whitespace can cause pypdf/_reader.py and pypdf/generic/_base.py to scan excessive input through read_until_whitespace, resulting in long runtimes and application unavailability.

    Update Pypdf to version 6.18.0.

    Affected
    • Pypdf lt *..6.18.0
    Fixed in
    • Pypdf 6.18.0

    Not sure whether and how you are affected? Ask a question about this vulnerability

    Metrics

    8.7

    Priority

    XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.

    Source: Vendor (CNA), CVSS v4

    7.5

    CVSS v3

    Severity High on the scale from 0 to 10.

    0.3 %

    EPSS score

    Low — model estimates < 1% exploitation likelihood.

    Source: FIRST EPSS, percentile 26.4

    Show all metrics
    Severity
    High
    Priority score

    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
    78.61
    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
    8.7
    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
    7.5
    CVSS v4

    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
    8.7
    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
    0.3 %
    Low — model estimates < 1% 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
    26.4
    Elevated — this CVE ranks above at least 10% of all CVEs scored today.
    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
    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-400, CWE-407

    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
    High technical severity: assess and remediate the vulnerability in vulnerability handling under Art. 21(2)(e) NIS2 and document the decision.
    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

    pypdf is a free and open-source pure-python PDF library. Prior to 6.18.0, a crafted PDF containing indirect-object identifiers or generation-number tokens that continue for a long time without whitespace can cause pypdf/_reader.py and pypdf/generic/_base.py to scan excessive input through read_until_whitespace, resulting in long runtimes and application unavailability. This issue is fixed in version 6.18.0.

    Source: BSI WID Portal

    Affected products

    The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

    Affected products
    VendorProductAffected versionsFixed in
    —URI
    • < 5.36
    • 5.36
    py-pdfpypdf
    • < 6.18.0
    • < 6.19.0
    • 6.18.0
    • 6.19.0
    urllib3urllib3
    • ≥ 1.10.3, < 2.8.0
    • ≥ 1.26.0, < 2.8.0
    • —
    • —
    pypdf_projectpypdf
    • < 6.18.0
    • < 6.19.0
    • 6.18.0
    • 6.19.0
    pythonurllib3
    • 1.10.3 – < 2.8.0
    • 1.26.0 – < 2.8.0
    • 2.8.0
    • 2.8.0
    Red HatEnterprise Linux
    • 10
    • 8
    • 9
    • —
    • —
    • —

    Affected operating systems

    Affected operating systems
    FamilyVendorProductVersion
    Linuxubuntupython-urllib3bionic
    Linuxubuntupython-urllib3focal
    Linuxubuntupython-urllib3jammy
    Linuxubuntupython-urllib3noble
    Linuxubuntupython-urllib3resolute

    Weakness classes (CWE)

    • CWE-400Uncontrolled Resource Consumption

      Class

      The product does not properly control the allocation and maintenance of a limited resource.

      Entry at MITRE CWE-400

    • CWE-407Inefficient Algorithmic Complexity

      Class

      An algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached.

      Entry at MITRE CWE-407

    References & sources

    • github.compy-pdf/pypdf/security/advisories/GHSA-5jq2-8x83-x246x_refsource_CONFIRM
    • github.compy-pdf/pypdf/pull/4055x_refsource_MISC
    • github.compy-pdf/pypdf/commit/82501d2993c6387833c4949d205caeb188f8bb9ex_refsource_MISC
    • github.compy-pdf/pypdf/releases/tag/6.18.0x_refsource_MISC
    • NVD (NIST)vuln/detail/CVE-2026-102994advisory
    • github.compy-pdf/pypdfpackage
    • pypi.orgproject/pypdfpackage
    • GitHub Security Advisoriesadvisories/GHSA-5jq2-8x83-x246advisory
    • github.comlibwww-perl/URI/commit/956619a9e94f86d8d2c529b4e06a3674c54a73e7…Patch
    • github.comlibwww-perl/URI/pull/191Issue tracking
    • metacpan.orgrelease/OALDERS/URI-5.36/changesRelease notes
    • rfc-editor.orgrfc/rfc5891Technical description
    • openwall.comlists/oss-security/2026/08/31/14
    • github.comurllib3/urllib3/security/advisories/GHSA-8988-9cw3-xx77x_refsource_CONFIRM
    • github.comurllib3/urllib3/pull/5093x_refsource_MISC
    • github.comurllib3/urllib3/commit/07408cec79d1856d81bb42c74a904a24fdb9e465x_refsource_MISC
    • github.comurllib3/urllib3/commit/b6447295fff7b38fdffc67e0df9712d60cef3cc3x_refsource_MISC
    • github.comurllib3/urllib3/releases/tag/2.8.0x_refsource_MISC
    • NVD (NIST)vuln/detail/CVE-2026-97687advisory
    • github.comurllib3/urllib3package

    Reanalysis & status changes

    Chronological NVD audit events for this CVE — reanalyses, CVSS updates, CPE diffs.

    1. Initial Analysisnvd@nist.gov

      • CVSS V3.1: after AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
      • CPE Configuration: after OR *cpe:2.3:a:pypdf_project:pypdf:*:*:*:*:*:*:*:* versions up to (excluding) 6.18.0
      • Reference Type: after GitHub, Inc.: https://github.com/py-pdf/pypdf/commit/82501d2993c6387833c4949d205caeb188f8bb9e Types: Patch
      • Reference Type: after GitHub, Inc.: https://github.com/py-pdf/pypdf/pull/4055 Types: Issue Tracking, Patch

    2. CVE Modified134c704f-9b21-4f2e-91b3-4a467353bcc0

      • SSVC: after {"id":"CVE-2026-102994","role":"CISA Coordinator","options":[{"exploitation":"none"},{"automatable":"yes"},{"technica…

    3. New CVE Receivedsecurity-advisories@github.com

      • Description: after pypdf is a free and open-source pure-python PDF library. Prior to 6.18.0, a crafted PDF containing indirect-object identifiers or generation-number tokens that continue for a long time without whitespace can cause pypdf/_reader.py and pypdf/generic/_base.py to scan excessive input through read_until_whitespace, resulting in long runtimes and application unavailability. This issue is fixed in version 6.18.0.
      • CVSS V4.0: after AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
      • CWE: after CWE-407
      • CWE: after CWE-400

    Linked CVEs

    Linked CVEs
    SeverityCVETitleCVSSExploitation
    HighCVE-2026-97689urllib3: HTTPResponse.stream()/read_chunked() buffers an unbounded chunk-size line into memory7.5—
    HighCVE-2026-97687urllib3: HTTPS proxy TLS configuration may be ignored or overridden8.1—
    MediumCVE-2026-19953URI: Improper Validation of Unsafe Equivalence in Input6.5—
    HighCVE-2026-102998pypdf: Possible long runtimes when generating appearance streams7.5—
    HighCVE-2026-102994pypdf: Possible long runtimes/large memory usage when parsing indirect objects7.5—