p PatchFirst

CVE-2026-97689

CVE-2026-97689 · urllib3: HTTPResponse.stream()/read_chunked() buffers an unbounded chunk-size line into memory

This page contains facts from public vulnerability sources. Check the original advisory before updating.

urllib3 is an HTTP client library for Python. From 1.10.3 until 2.8.0, the HTTPResponse.read_chunked and HTTPResponse.stream methods can allocate unbounded memory because the streaming chunk parser buffers the chunk-size field until newline or EOF without a length bound. The trigger is that a malicious server returns Transfer-Encoding: chunked followed by a very long run of bytes without a newline. The attack mechanism is that a malicious HTTP server sends a very long unterminated chunk-size line. The impact is that unbounded memory allocation can exhaust the client process. This issue is fixed in version 2.8.0.

CVSS 8.9 · High · EPSS 0.3% · Fix available

Published
Updated

Stack: system · python

Affected products and versions

  • urllib3

    Versions
    • >= 1.10.3, < 2.8.0: Affected

    No fix published

  • python-urllib3 Debian:12

    Versions
    • 1.26.12-1
    • 1.26.12-1+deb12u1
    • 1.26.12-1+deb12u2
    • 1.26.12-1+deb12u3
    • 1.26.12-1+deb12u4
    • 1.26.16-1
    • 1.26.17-1
    • 1.26.18-1
    • 1.26.18-2
    • 2.0.7-1
    • 2.0.7-2
    • 2.2.3-1
    • 2.2.3-2
    • 2.2.3-3
    • 2.2.3-4
    • 2.3.0-1
    • 2.3.0-2
    • 2.3.0-3
    • 2.5.0-1
    • 2.5.0-1.1
    • 2.5.0-2
    • 2.6.3-1
    • 2.6.3-2
    • 2.7.0-1
    • 2.7.0-2
    • 2.7.0-3
    • 2.8.0-1
    • 2.8.0-2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-urllib3 Debian:13

    Versions
    • 2.3.0-3
    • 2.3.0-3+deb13u1
    • 2.3.0-3+deb13u2
    • 2.5.0-1
    • 2.5.0-1.1
    • 2.5.0-2
    • 2.6.3-1
    • 2.6.3-2
    • 2.7.0-1
    • 2.7.0-2
    • 2.7.0-3
    • 2.8.0-1
    • 2.8.0-2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-urllib3 Debian:14

    Versions
    • 2.3.0-3
    • 2.5.0-1
    • 2.5.0-1.1
    • 2.5.0-2
    • 2.6.3-1
    • 2.6.3-2
    • 2.7.0-1
    • 2.7.0-2
    • 2.7.0-3
    Affected ranges
    • ECOSYSTEM: < 2.8.0-1

    Update to 2.8.0-1

  • urllib3 PyPI

    Versions
    • 1.10.3
    • 1.10.4
    • 1.11
    • 1.12
    • 1.13
    • 1.13.1
    • 1.14
    • 1.15
    • 1.15.1
    • 1.16
    • 1.17
    • 1.18
    • 1.18.1
    • 1.19
    • 1.19.1
    • 1.20
    • 1.21
    • 1.21.1
    • 1.22
    • 1.23
    • 1.24
    • 1.24.1
    • 1.24.2
    • 1.24.3
    • 1.25
    • 1.25.1
    • 1.25.10
    • 1.25.11
    • 1.25.2
    • 1.25.3
    • 1.25.4
    • 1.25.5
    • 1.25.6
    • 1.25.7
    • 1.25.8
    • 1.25.9
    • 1.26.0
    • 1.26.1
    • 1.26.10
    • 1.26.11
    • 1.26.12
    • 1.26.13
    • 1.26.14
    • 1.26.15
    • 1.26.16
    • 1.26.17
    • 1.26.18
    • 1.26.19
    • 1.26.2
    • 1.26.20
    • 1.26.3
    • 1.26.4
    • 1.26.5
    • 1.26.6
    • 1.26.7
    • 1.26.8
    • 1.26.9
    • 2.0.0
    • 2.0.0a1
    • 2.0.0a2
    • 2.0.0a3
    • 2.0.0a4
    • 2.0.1
    • 2.0.2
    • 2.0.3
    • 2.0.4
    • 2.0.5
    • 2.0.6
    • 2.0.7
    • 2.1.0
    • 2.2.0
    • 2.2.1
    • 2.2.2
    • 2.2.3
    • 2.3.0
    • 2.4.0
    • 2.5.0
    • 2.6.0
    • 2.6.1
    • 2.6.2
    • 2.6.3
    • 2.7.0
    Affected ranges
    • ECOSYSTEM: ≥ 1.10.3, < 2.8.0

    Update to 2.8.0

  • python-pip Ubuntu:Pro:14.04:LTS

    Versions
    • 1.4.1-2
    • 1.5.4-1
    • 1.5.4-1ubuntu1
    • 1.5.4-1ubuntu3
    • 1.5.4-1ubuntu4
    • 1.5.4-1ubuntu4+esm1
    • 1.5.4-1ubuntu4+esm2
    • 1.5.4-1ubuntu4+esm3
    • 1.5.4-1ubuntu4+esm4
    • 1.5.4-1ubuntu4+esm5
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-urllib3 Ubuntu:Pro:16.04:LTS

    Versions
    • 1.11-1
    • 1.12-1
    • 1.13.1-1
    • 1.13.1-2
    • 1.13.1-2ubuntu0.16.04.1
    • 1.13.1-2ubuntu0.16.04.2
    • 1.13.1-2ubuntu0.16.04.3
    • 1.13.1-2ubuntu0.16.04.4
    • 1.13.1-2ubuntu0.16.04.4+esm1
    • 1.13.1-2ubuntu0.16.04.4+esm2
    • 1.13.1-2ubuntu0.16.04.4+esm3
    • 1.13.1-2ubuntu0.16.04.4+esm4
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-pip Ubuntu:Pro:16.04:LTS

    Versions
    • 1.5.6-7ubuntu1
    • 1.5.6-7ubuntu2
    • 8.0.2-7
    • 8.0.3-1
    • 8.0.3-2
    • 8.1.0-1
    • 8.1.0-2
    • 8.1.1-1
    • 8.1.1-2
    • 8.1.1-2ubuntu0.1
    • 8.1.1-2ubuntu0.2
    • 8.1.1-2ubuntu0.4
    • 8.1.1-2ubuntu0.6
    • 8.1.1-2ubuntu0.6+esm2
    • 8.1.1-2ubuntu0.6+esm3
    • 8.1.1-2ubuntu0.6+esm4
    • 8.1.1-2ubuntu0.6+esm5
    • 8.1.1-2ubuntu0.6+esm6
    • 8.1.1-2ubuntu0.6+esm8
    • 8.1.1-2ubuntu0.6+esm10
    • 8.1.1-2ubuntu0.6+esm11
    • 8.1.1-2ubuntu0.6+esm12
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-urllib3 Ubuntu:Pro:18.04:LTS

    Versions
    • 1.21.1-1
    • 1.22-1
    • 1.22-1ubuntu0.18.04.1
    • 1.22-1ubuntu0.18.04.2
    • 1.22-1ubuntu0.18.04.2+esm1
    • 1.22-1ubuntu0.18.04.2+esm2
    • 1.22-1ubuntu0.18.04.2+esm3
    • 1.22-1ubuntu0.18.04.2+esm4
    Affected ranges
    • ECOSYSTEM: < 1.22-1ubuntu0.18.04.2+esm5

    Update to 1.22-1ubuntu0.18.04.2+esm5

  • python-pip Ubuntu:Pro:18.04:LTS

    Versions
    • 9.0.1-2
    • 9.0.1-2.3~ubuntu1
    • 9.0.1-2.3~ubuntu1.18.04.1
    • 9.0.1-2.3~ubuntu1.18.04.2
    • 9.0.1-2.3~ubuntu1.18.04.3
    • 9.0.1-2.3~ubuntu1.18.04.4
    • 9.0.1-2.3~ubuntu1.18.04.5
    • 9.0.1-2.3~ubuntu1.18.04.5+esm2
    • 9.0.1-2.3~ubuntu1.18.04.5+esm3
    • 9.0.1-2.3~ubuntu1.18.04.6
    • 9.0.1-2.3~ubuntu1.18.04.6+esm1
    • 9.0.1-2.3~ubuntu1.18.04.7
    • 9.0.1-2.3~ubuntu1.18.04.7+esm1
    • 9.0.1-2.3~ubuntu1.18.04.8
    • 9.0.1-2.3~ubuntu1.18.04.8+esm1
    • 9.0.1-2.3~ubuntu1.18.04.8+esm2
    • 9.0.1-2.3~ubuntu1.18.04.8+esm4
    • 9.0.1-2.3~ubuntu1.18.04.8+esm6
    • 9.0.1-2.3~ubuntu1.18.04.8+esm7
    • 9.0.1-2.3~ubuntu1.18.04.8+esm8
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-urllib3 Ubuntu:Pro:20.04:LTS

    Versions
    • 1.24.1-1ubuntu1
    • 1.24.1-1ubuntu2
    • 1.25.8-1
    • 1.25.8-2
    • 1.25.8-2ubuntu0.1
    • 1.25.8-2ubuntu0.2
    • 1.25.8-2ubuntu0.3
    • 1.25.8-2ubuntu0.4
    • 1.25.8-2ubuntu0.4+esm1
    • 1.25.8-2ubuntu0.4+esm2
    • 1.25.8-2ubuntu0.4+esm3
    • 1.25.8-2ubuntu0.4+esm4
    • 1.25.8-2ubuntu0.4+esm5
    Affected ranges
    • ECOSYSTEM: < 1.25.8-2ubuntu0.4+esm6

    Update to 1.25.8-2ubuntu0.4+esm6

  • python-pip Ubuntu:Pro:20.04:LTS

    Versions
    • 18.1-5
    • 18.1-5build1
    • 18.1-5ubuntu1
    • 20.0.2-2
    • 20.0.2-4
    • 20.0.2-5
    • 20.0.2-5ubuntu1
    • 20.0.2-5ubuntu1.1
    • 20.0.2-5ubuntu1.3
    • 20.0.2-5ubuntu1.4
    • 20.0.2-5ubuntu1.5
    • 20.0.2-5ubuntu1.6
    • 20.0.2-5ubuntu1.7
    • 20.0.2-5ubuntu1.8
    • 20.0.2-5ubuntu1.9
    • 20.0.2-5ubuntu1.10
    • 20.0.2-5ubuntu1.10+esm2
    • 20.0.2-5ubuntu1.11
    • 20.0.2-5ubuntu1.11+esm2
    • 20.0.2-5ubuntu1.11+esm3
    • 20.0.2-5ubuntu1.11+esm4
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-urllib3 Ubuntu:22.04:LTS

    Versions
    • 1.26.5-1~exp1
    • 1.26.5-1~exp1ubuntu0.1
    • 1.26.5-1~exp1ubuntu0.2
    • 1.26.5-1~exp1ubuntu0.3
    • 1.26.5-1~exp1ubuntu0.4
    • 1.26.5-1~exp1ubuntu0.5
    • 1.26.5-1~exp1ubuntu0.6
    • 1.26.5-1~exp1ubuntu0.7
    Affected ranges
    • ECOSYSTEM: < 1.26.5-1~exp1ubuntu0.8

    Update to 1.26.5-1~exp1ubuntu0.8

  • python-pip Ubuntu:Pro:22.04:LTS

    Versions
    • 20.3.4-4
    • 21.3.1+dfsg-3
    • 22.0.2+dfsg-1
    • 22.0.2+dfsg-1ubuntu0.1
    • 22.0.2+dfsg-1ubuntu0.2
    • 22.0.2+dfsg-1ubuntu0.3
    • 22.0.2+dfsg-1ubuntu0.4
    • 22.0.2+dfsg-1ubuntu0.5
    • 22.0.2+dfsg-1ubuntu0.6
    • 22.0.2+dfsg-1ubuntu0.7
    • 22.0.2+dfsg-1ubuntu0.7+esm1
    • 22.0.2+dfsg-1ubuntu0.7+esm2
    • 22.0.2+dfsg-1ubuntu0.7+esm3
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-urllib3 Ubuntu:24.04:LTS

    Versions
    • 1.26.16-1
    • 1.26.18-1
    • 2.0.7-1
    • 2.0.7-1ubuntu0.1
    • 2.0.7-1ubuntu0.2
    • 2.0.7-1ubuntu0.3
    • 2.0.7-1ubuntu0.4
    • 2.0.7-1ubuntu0.5
    • 2.0.7-1ubuntu0.6
    • 2.0.7-1ubuntu0.7
    Affected ranges
    • ECOSYSTEM: < 2.0.7-1ubuntu0.8

    Update to 2.0.7-1ubuntu0.8

  • python-pip Ubuntu:Pro:24.04:LTS

    Versions
    • 23.2+dfsg-1
    • 23.3+dfsg-1
    • 24.0+dfsg-1
    • 24.0+dfsg-1ubuntu1
    • 24.0+dfsg-1ubuntu1.1
    • 24.0+dfsg-1ubuntu1.2
    • 24.0+dfsg-1ubuntu1.3
    • 24.0+dfsg-1ubuntu1.3+esm1
    • 24.0+dfsg-1ubuntu1.3+esm2
    • 24.0+dfsg-1ubuntu1.3+esm3
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-pip Ubuntu:26.10

    Versions
    • 25.1.1+dfsg-1ubuntu2
    • 26.1.2+dfsg-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-urllib3 Ubuntu:26.04:LTS

    Versions
    • 2.3.0-3
    • 2.5.0-1
    • 2.5.0-1ubuntu1
    • 2.5.0-1ubuntu2
    • 2.6.3-1ubuntu1
    • 2.6.3-1ubuntu1.1
    Affected ranges
    • ECOSYSTEM: < 2.6.3-1ubuntu1.2

    Update to 2.6.3-1ubuntu1.2

  • python-pip Ubuntu:Pro:26.04:LTS

    Versions
    • 25.1.1+dfsg-1ubuntu2
    • 25.1.1+dfsg-1ubuntu2+esm1
    • 25.1.1+dfsg-1ubuntu2+esm2
    • 25.1.1+dfsg-1ubuntu2+esm3
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

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