CVE-2026-23457

HIGHPre-NVD 8.68.6—
EchelonGraph scoreMEDIUM confidence

Score 8.6 from GitHub Security Advisory (severity: HIGH) published 2026-04-03. a secondary CVSS source baseline 8.6; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
8.6EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 8.6Exploit: None knownExposed: 0

A fix is available — apply it.

In the Linux kernel, the following vulnerability has been resolved:

netfilter: nf_conntrack_sip: fix Content-Length u32 truncation in sip_help_tcp()

sip_help_tcp() parses the SIP Content-Length header with simple_strtoul(), which returns unsigned long, but stores the result in unsigned int clen. On 64-bit systems, values exceeding UINT_MAX are silently truncated before computing the SIP message boundary.

For example, Content-Length 4294967328 (2^32 + 32) is truncated to 32, causing the parser to miscalculate where the current message ends. The loop then treats trailing data in the TCP segment as a second SIP message and processes it through the SDP parser.

Fix this by changing clen to unsigned long to match the return type of simple_strtoul(), and reject Content-Length values that exceed the remaining TCP payload length.

CVSS v3
8.6
EG Score
8.6(medium)
EG Risk
43(Track)
EG Risk 43/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity86% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
35%
KEV
Not listed

Published

April 3, 2026

Last Modified

July 24, 2026

Advisory Details (8)

Auto-updated May 3, 2026
No patch confirmed yet.
generic

netfilter: nf_conntrack_sip: fix Content-Length u32 truncation in sip_help_tcp() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/fbce58e719a17aa215c724473fd5baaa4a8dc57c
generic

netfilter: nf_conntrack_sip: fix Content-Length u32 truncation in sip_help_tcp() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/ed81b6a7012485acdb9c6c80735a0b7d8e5e1873
generic

netfilter: nf_conntrack_sip: fix Content-Length u32 truncation in sip_help_tcp() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/d4f17256544cc37f6534a14a27a9dec3540c2015
generic

netfilter: nf_conntrack_sip: fix Content-Length u32 truncation in sip_help_tcp() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/cd1b7403ec835f8a0b3f1f7e68ac26af2cb1e42f
generic

netfilter: nf_conntrack_sip: fix Content-Length u32 truncation in sip_help_tcp() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/b75209debb9adab287b3caa982f77788c1e15027
generic

netfilter: nf_conntrack_sip: fix Content-Length u32 truncation in sip_help_tcp() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/865dba58958c3a86786f89a501971ab0e3ec6ba9
generic

netfilter: nf_conntrack_sip: fix Content-Length u32 truncation in sip_help_tcp() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/75fcaee5170e7dbbee778927134ef2e9568b4659
generic

netfilter: nf_conntrack_sip: fix Content-Length u32 truncation in sip_help_tcp() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/528b4509c9dfc272e2e92d811915e5211650d383

Vendor Advisories for CVE-2026-23457(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(18)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-virtual-6.8 (6.8.0-136.136) @ noble2026-07-26ubuntu
ubuntulinux-tools-gcp-fips-6.8 (6.8.0-1064.72+fips1) @ noble2026-07-26ubuntu
ubuntulinux-xilinx-zynqmp-tools-5.15.0-1075 (5.15.0-1075.79) @ jammy2026-07-26ubuntu
ubuntulinux-tools-ibm-edge (5.15.0.1106.110~20.04.1) @ focal2026-07-26ubuntu
ubuntulinux-tools-azure-edge (6.8.0-1063.71~22.04.1) @ jammy2026-07-26ubuntu
ubuntulinux-tools-aws-lts-24.04 (6.8.0-1061.64+1) @ noble2026-07-26ubuntu
ubuntulinux-tools-nvidia-tegra-rt-5.15 (5.15.0.1064.64) @ jammy2026-07-26ubuntu
ubuntulinux-tools-nvidia-tegra-rt-5.15 (5.15.0.1064.66~20.04.1) @ focal2026-07-26ubuntu
ubuntulinux-tools-oracle-lts-24.04 (6.8.0-1058.61) @ noble2026-07-26ubuntu
ubuntulinux-tools-oracle-edge (6.8.0-1058.61~22.04.1) @ jammy2026-07-26ubuntu
ubuntulinux-tools-nvidia-lowlatency-5.15 (5.15.0.1107.107) @ jammy2026-07-26ubuntu
ubuntulinux-tools-nvidia-lowlatency-64k-6.8 (6.8.0-1059.62.1) @ noble2026-07-26ubuntu
ubuntulinux-tools-azure-fde-lts-24.04 (6.8.0-1062.69) @ noble2026-07-26ubuntu
ubuntulinux-tools-azure-fde-6.8 (6.8.0-1062.69~22.04.1) @ jammy2026-07-26ubuntu
ubuntulinux-tools-oracle-lts-22.04 (5.15.0.1109.105) @ jammy2026-07-26ubuntu
ubuntulinux-tools-azure-fde-lts-22.04 (5.15.0.1117.126) @ jammy2026-07-26ubuntu
ubuntulinux-tools-azure-fips-6.8 (6.8.0-1063.71+fips2) @ noble2026-07-26ubuntu
linuxKernel @ 5.10.253—osv

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

All Vendor Advisories

(17)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 15× in last 7d / 51× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 136 total refreshes for this CVE.

  1. 2026-07-27 14:13 UTCEPSS rescore
  2. 2026-07-26 14:54 UTCEPSS rescore
  3. 2026-07-26 14:54 UTCEPSS rescore
  4. 2026-07-26 09:18 UTCEG score recompute
  5. 2026-07-26 09:18 UTCVendor advisory
  6. 2026-07-26 09:18 UTCGHSA enrichment
  7. 2026-07-25 14:17 UTCEPSS rescore
  8. 2026-07-25 14:17 UTCEPSS rescore
  9. 2026-07-24 14:17 UTCEPSS rescore
  10. 2026-07-23 14:18 UTCEPSS rescore
  11. 2026-07-23 14:18 UTCEPSS rescore
  12. 2026-07-23 03:07 UTCEG score recompute
  13. 2026-07-22 14:08 UTCEPSS rescore
  14. 2026-07-21 15:24 UTCEPSS rescore
  15. 2026-07-21 15:24 UTCEPSS rescore
  16. 2026-07-20 17:08 UTCEPSS rescore
  17. 2026-07-19 14:31 UTCEPSS rescore
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  19. 2026-07-19 02:29 UTCEPSS rescore
  20. 2026-07-19 02:28 UTCEPSS rescore
  21. 2026-07-18 10:04 UTCEPSS rescore
  22. 2026-07-18 10:04 UTCEPSS rescore
  23. 2026-07-17 03:24 UTCOSV refresh
  24. 2026-07-16 17:03 UTCEPSS rescore
  25. 2026-07-16 17:03 UTCEPSS rescore
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  1. 2026-07-15 16:57 UTCEPSS rescore
  2. 2026-07-15 16:57 UTCEPSS rescore
  3. 2026-07-15 02:00 UTCEPSS rescore
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  5. 2026-07-13 22:30 UTCEPSS rescore
  6. 2026-07-13 06:13 UTCEPSS rescore
  7. 2026-07-13 06:13 UTCEPSS rescore
  8. 2026-07-12 05:46 UTCEPSS rescore
  9. 2026-07-12 05:46 UTCEPSS rescore
  10. 2026-07-11 08:27 UTCEPSS rescore
  11. 2026-07-09 19:10 UTCEPSS rescore
  12. 2026-07-08 15:15 UTCEPSS rescore
  13. 2026-07-08 15:15 UTCEPSS rescore
  14. 2026-07-07 13:46 UTCEPSS rescore
  15. 2026-07-06 16:27 UTCEPSS rescore
  16. 2026-07-06 16:27 UTCEPSS rescore
  17. 2026-07-06 02:23 UTCEPSS rescore
  18. 2026-07-06 02:23 UTCEPSS rescore
  19. 2026-07-05 02:30 UTCEPSS rescore
  20. 2026-07-04 06:31 UTCEPSS rescore
  21. 2026-07-04 06:31 UTCEPSS rescore
  22. 2026-07-01 15:06 UTCEPSS rescore
  23. 2026-07-01 15:06 UTCEPSS rescore
  24. 2026-06-30 23:22 UTCEPSS rescore
  25. 2026-06-30 23:22 UTCEPSS rescore
  26. 2026-06-29 14:06 UTCEPSS rescore
  27. 2026-06-28 14:07 UTCEPSS rescore
  28. 2026-06-28 14:07 UTCEPSS rescore
  29. 2026-06-28 04:56 UTCEPSS rescore
  30. 2026-06-28 04:56 UTCEPSS rescore
  31. 2026-06-27 03:08 UTCEPSS rescore
  32. 2026-06-25 13:49 UTCEPSS rescore
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  34. 2026-06-24 14:05 UTCEPSS rescore
  35. 2026-06-24 14:05 UTCEPSS rescore
  36. 2026-06-23 21:33 UTCEPSS rescore
  37. 2026-06-23 21:32 UTCEPSS rescore
  38. 2026-06-22 14:25 UTCEPSS rescore
  39. 2026-06-22 14:25 UTCEPSS rescore
  40. 2026-06-21 14:56 UTCEPSS rescore
  41. 2026-06-21 14:56 UTCEPSS rescore
  42. 2026-06-21 01:59 UTCEPSS rescore
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  44. 2026-06-19 19:25 UTCEPSS rescore
  45. 2026-06-19 19:25 UTCEPSS rescore
  46. 2026-06-18 17:52 UTCEPSS rescore
  47. 2026-06-17 17:53 UTCEPSS rescore
  48. 2026-06-17 17:53 UTCEPSS rescore
  49. 2026-06-16 17:52 UTCEPSS rescore
  50. 2026-06-15 17:48 UTCEPSS rescore
  51. 2026-06-14 23:18 UTCEPSS rescore
  52. 2026-06-13 23:00 UTCEPSS rescore
  53. 2026-06-12 23:12 UTCEPSS rescore
  54. 2026-06-12 23:12 UTCEPSS rescore
  55. 2026-06-11 22:02 UTCGHSA enrichment
  56. 2026-06-11 14:00 UTCEPSS rescore
  57. 2026-06-10 22:18 UTCEPSS rescore
  58. 2026-06-10 13:37 UTCGHSA enrichment
  59. 2026-06-10 13:22 UTCEPSS rescore
  60. 2026-06-10 02:00 UTCGHSA enrichment
  61. 2026-06-09 14:32 UTCGHSA enrichment
  62. 2026-06-08 14:17 UTCEPSS rescore
  63. 2026-06-08 14:17 UTCEPSS rescore
  64. 2026-06-08 09:51 UTCGHSA enrichment
  65. 2026-06-07 22:24 UTCGHSA enrichment
  66. 2026-06-07 15:25 UTCEPSS rescore
  67. 2026-06-07 15:24 UTCEPSS rescore
  68. 2026-06-07 10:56 UTCGHSA enrichment
  69. 2026-06-06 13:47 UTCEPSS rescore
  70. 2026-06-06 13:47 UTCEPSS rescore
  71. 2026-06-06 13:47 UTCEPSS rescore
  72. 2026-06-05 22:47 UTCEPSS rescore
  73. 2026-06-05 06:10 UTCEPSS rescore
  74. 2026-06-05 06:10 UTCEPSS rescore
  75. 2026-06-04 13:12 UTCEPSS rescore

Frequently asked(5)

What is CVE-2026-23457?
CVE-2026-23457 is a high vulnerability published on April 3, 2026. In the Linux kernel, the following vulnerability has been resolved: netfilter: nfconntracksip: fix Content-Length u32 truncation in siphelptcp() siphelptcp() parses the SIP Content-Length header with simple_strtoul(), which returns unsigned long, but stores the result in unsigned int clen. On…
When was CVE-2026-23457 disclosed?
CVE-2026-23457 was first published in the National Vulnerability Database on April 3, 2026, with the most recent update on July 24, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-23457 actively exploited?
CVE-2026-23457 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 64.5% of all scored CVEs.
What is the CVSS score of CVE-2026-23457?
CVE-2026-23457 has a CVSS v3 base score of 8.6 (NVD).
How do I remediate CVE-2026-23457?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-23457, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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