CVE-2026-52993

CRITICALPre-NVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-06-24. the CNA's CVSS baseline 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cna:linux, epss, ghsa
Trending — 4 sources updated this week
9.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 9.8Exploit: None knownExposed: 0

A fix is available — apply it.

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

tipc: fix double-free in tipc_buf_append()

tipc_msg_validate() can potentially reallocate the skb it is validating, freeing the old one. In tipc_buf_append(), it was being called with a pointer to a local variable which was a copy of the caller's skb pointer.

If the skb was reallocated and validation subsequently failed, the error handling path would free the original skb pointer, which had already been freed, leading to double-free.

Fix this by checking if head now points to a newly allocated reassembled skb. If it does, reassign *headbuf for later freeing operations.

CVSS v3
9.8
EG Score
9.8(medium)
EG Risk
49(Track)
EG Risk 49/100SSVC: 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
Severity98% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
31%
KEV
Not listed

Published

June 24, 2026

Last Modified

August 5, 2026

Advisory Details (12)

Auto-updated Sep 16, 2026
No patch confirmed yet.
generic

tipc: fix double-free in tipc_buf_append() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/d293ca716e7d5dffdaecaf6b9b2f857a33dc3d3a
generic

tipc: fix double-free in tipc_buf_append() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/29940fff14110ca48c5ccc168d121665b51bb778
generic

tipc: fix double-free in tipc_buf_append() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/1d5e589055880fae229e229e1929e087dbe08cf3
generic

tipc: fix double-free in tipc_buf_append() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/4d104882bc815d4ec666ace9155f5f52715879a6
generic

tipc: fix double-free in tipc_buf_append() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/0274f24485fc38032d4093e463dc3ff5c7a667c9
generic

tipc: fix double-free in tipc_buf_append() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/d3556656c6daebf8def751c7e71d11dd0a180d24
generic

tipc: fix double-free in tipc_buf_append() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/4ee4deadaae7cb2e3d53af0fc889cf92a73413c0
generic

tipc: fix double-free in tipc_buf_append() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/a438975a6dcdbd70865978c021650d1485586f0b
redhat Patch Available

Affected: Red Hat Enterprise Linux 8.

https://access.redhat.com/errata/RHSA-2026:45116
redhat Patch Available

Affected: Red Hat Enterprise Linux 8.10 Extended Update Support.

https://access.redhat.com/errata/RHSA-2026:45115
redhat Patch Available

cve-details

https://access.redhat.com/security/cve/CVE-2026-52993
redhat

2492437 – (CVE-2026-52993) CVE-2026-52993 kernel: tipc: fix double-free in tipc_buf_append()

https://bugzilla.redhat.com/show_bug.cgi?id=2492437

Vendor Advisories for CVE-2026-52993(6)

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

Patch Availability(30)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-tools-azure (4.15.0.1206.221~14.04.1) @ trusty2026-09-18ubuntu
ubuntulinux-virtual-6.8 (6.8.0-136.136) @ noble2026-09-18ubuntu
ubuntulinux-tools-azure-fips-5.4 (5.4.0.1167.103) @ focal2026-09-18ubuntu
ubuntulinux-tools-gcp-fips-5.4 (5.4.0.1165.107) @ focal2026-09-18ubuntu
ubuntulinux-virtual-hwe-24.04-edge (7.0.0-28.28~24.04.1) @ noble2026-09-18ubuntu
ubuntulinux-virtual-hwe-26.04-edge (7.0.0-28.28) @ resolute2026-09-18ubuntu
ubuntulinux-tools-gcp-fips-6.8 (6.8.0-1064.72+fips1) @ noble2026-09-18ubuntu
ubuntulinux-virtual-hwe-20.04-edge (5.15.0.186.196~20.04.1) @ focal2026-09-18ubuntu
ubuntulinux-tools-oracle-7.0 (7.0.0-1008.8) @ resolute2026-09-18ubuntu
ubuntulinux-tools-nvidia-tegra-rt-5.15 (5.15.0.1064.66~20.04.1) @ focal2026-09-18ubuntu
ubuntulinux-tools-lowlatency-hwe-22.04-edge (6.8.0-136.136.2~22.04.1) @ jammy2026-09-18ubuntu
ubuntulinux-tools-oracle-edge (6.8.0-1058.61~22.04.1) @ jammy2026-09-18ubuntu
ubuntulinux-tools-raspi-realtime-7.0 (7.0.0-1015.15) @ resolute2026-09-18ubuntu
ubuntulinux-tools-nvidia-lowlatency-64k-6.8 (6.8.0-1059.62.1) @ noble2026-09-18ubuntu
ubuntulinux-tools-nvidia-lowlatency-5.15 (5.15.0.1107.107) @ jammy2026-09-18ubuntu
ubuntulinux-tools-nvidia-tegra-rt-5.15 (5.15.0.1064.64) @ jammy2026-09-18ubuntu
ubuntulinux-tools-azure-fde-7.0 (7.0.0-1009.9) @ resolute2026-09-18ubuntu
ubuntulinux-tools-aws-lts-24.04 (6.8.0-1061.64+1) @ noble2026-09-18ubuntu
ubuntulinux-tools-azure-lts-24.04 (6.8.0-1063.71) @ noble2026-09-18ubuntu
ubuntulinux-tools-azure-fde-lts-24.04 (6.8.0-1062.69) @ noble2026-09-18ubuntu
ubuntulinux-tools-azure-fde-6.8 (6.8.0-1062.69~22.04.1) @ jammy2026-09-18ubuntu
ubuntulinux-tools-oracle-lts-22.04 (5.15.0.1109.105) @ jammy2026-09-18ubuntu
ubuntulinux-tools-azure-fde-lts-22.04 (5.15.0.1117.126) @ jammy2026-09-18ubuntu
ubuntulinux-tools-aws-edge (6.8.0-1061.64~22.04.1) @ jammy2026-09-18ubuntu
ubuntulinux-xilinx-zynqmp (6.8.0.1033.34) @ noble2026-09-18ubuntu
ubuntulinux-virtual-hwe-22.04-edge (6.8.0-136.136~22.04.1) @ jammy2026-09-18ubuntu
redhatkernel-0:5.14.0-687.33.1.el9_82026-07-31redhat
redhatkernel-0:6.12.0-211.40.1.el10_22026-07-28redhat
redhatkernel-rt-0:4.18.0-553.147.1.rt7.488.el8_102026-07-24redhat
redhatkernel-0:4.18.0-553.147.1.el8_102026-07-24redhat

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.

Affected Packages

(5 across 4 ecosystems)
Debian:11(2)
PackageVulnerable rangeFixed inDependents
linux5.10.103-1 ... 5.10.92-2 (54 versions)5.10.259-1—
linux-6.16.1.106-3~deb11u1 ... 6.1.174-1~deb11u1 (20 versions)6.1.176-1~deb11u1—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
linux6.1.106-1 ... 6.1.99-1 (53 versions)6.1.176-1—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
linux6.12.38-1 ... 6.12.94-1~bpo12+1 (27 versions)6.12.94-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 7.0.9-1~bpo13+1 (140 versions)7.0.10-1—

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Additional Vendor Advisories

(20)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 19× in last 7d / 94× 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 582 total refreshes for this CVE.

  1. 2026-09-18 19:28 UTCEPSS rescore
  2. 2026-09-18 08:05 UTCEG score recompute
  3. 2026-09-18 08:05 UTCVendor advisory
  4. 2026-09-18 08:04 UTCGHSA enrichment
  5. 2026-09-16 14:08 UTCEPSS rescore
  6. 2026-09-16 05:15 UTCEPSS rescore
  7. 2026-09-14 05:57 UTCVendor advisory
  8. 2026-09-14 05:56 UTCGHSA enrichment
  9. 2026-09-14 01:52 UTCEG score recompute
  10. 2026-09-14 01:52 UTCVendor advisory
  11. 2026-09-14 01:52 UTCGHSA enrichment
  12. 2026-09-13 16:47 UTCEPSS rescore
  13. 2026-09-13 14:03 UTCVendor advisory
  14. 2026-09-13 14:02 UTCGHSA enrichment
  15. 2026-09-13 09:58 UTCVendor advisory
  16. 2026-09-13 09:58 UTCGHSA enrichment
  17. 2026-09-12 16:58 UTCEG score recompute
  18. 2026-09-12 16:58 UTCVendor advisory
  19. 2026-09-12 16:58 UTCGHSA enrichment
  20. 2026-09-11 14:53 UTCEPSS rescore
  21. 2026-09-10 09:35 UTCEPSS rescore
  22. 2026-09-08 22:01 UTCEPSS rescore
  23. 2026-09-07 16:01 UTCEPSS rescore
  24. 2026-09-06 13:47 UTCEPSS rescore
  25. 2026-09-04 05:06 UTCEPSS rescore
Show 75 more
  1. 2026-09-02 14:12 UTCEPSS rescore
  2. 2026-09-01 13:54 UTCEPSS rescore
  3. 2026-09-01 04:40 UTCEPSS rescore
  4. 2026-08-31 00:17 UTCVendor advisory
  5. 2026-08-31 00:16 UTCGHSA enrichment
  6. 2026-08-30 20:12 UTCEG score recompute
  7. 2026-08-30 20:12 UTCVendor advisory
  8. 2026-08-30 20:11 UTCGHSA enrichment
  9. 2026-08-30 19:17 UTCEPSS rescore
  10. 2026-08-30 01:22 UTCEPSS rescore
  11. 2026-08-28 21:41 UTCEPSS rescore
  12. 2026-08-28 04:47 UTCEG score recompute
  13. 2026-08-28 04:47 UTCVendor advisory
  14. 2026-08-28 04:46 UTCGHSA enrichment
  15. 2026-08-27 14:25 UTCEPSS rescore
  16. 2026-08-26 14:46 UTCEPSS rescore
  17. 2026-08-25 13:49 UTCEPSS rescore
  18. 2026-08-25 06:15 UTCVendor advisory
  19. 2026-08-25 06:14 UTCGHSA enrichment
  20. 2026-08-25 02:05 UTCVendor advisory
  21. 2026-08-25 02:04 UTCGHSA enrichment
  22. 2026-08-24 22:00 UTCEG score recompute
  23. 2026-08-24 22:00 UTCVendor advisory
  24. 2026-08-24 21:59 UTCGHSA enrichment
  25. 2026-08-24 13:43 UTCEG score recompute
  26. 2026-08-24 13:43 UTCVendor advisory
  27. 2026-08-24 13:42 UTCGHSA enrichment
  28. 2026-08-24 04:37 UTCVendor advisory
  29. 2026-08-24 04:37 UTCGHSA enrichment
  30. 2026-08-24 00:10 UTCVendor advisory
  31. 2026-08-24 00:10 UTCGHSA enrichment
  32. 2026-08-23 20:05 UTCVendor advisory
  33. 2026-08-23 20:04 UTCGHSA enrichment
  34. 2026-08-23 16:00 UTCVendor advisory
  35. 2026-08-23 16:00 UTCGHSA enrichment
  36. 2026-08-23 11:56 UTCVendor advisory
  37. 2026-08-23 11:56 UTCGHSA enrichment
  38. 2026-08-23 07:52 UTCVendor advisory
  39. 2026-08-23 07:51 UTCGHSA enrichment
  40. 2026-08-23 02:48 UTCEG score recompute
  41. 2026-08-23 02:48 UTCVendor advisory
  42. 2026-08-23 02:47 UTCGHSA enrichment
  43. 2026-08-23 00:19 UTCEPSS rescore
  44. 2026-08-22 22:42 UTCVendor advisory
  45. 2026-08-22 22:42 UTCGHSA enrichment
  46. 2026-08-22 13:07 UTCEG score recompute
  47. 2026-08-22 13:07 UTCVendor advisory
  48. 2026-08-22 13:07 UTCGHSA enrichment
  49. 2026-08-21 23:49 UTCEPSS rescore
  50. 2026-08-21 22:22 UTCVendor advisory
  51. 2026-08-21 22:22 UTCGHSA enrichment
  52. 2026-08-21 18:18 UTCVendor advisory
  53. 2026-08-21 18:17 UTCGHSA enrichment
  54. 2026-08-21 14:13 UTCVendor advisory
  55. 2026-08-21 14:12 UTCGHSA enrichment
  56. 2026-08-21 09:19 UTCVendor advisory
  57. 2026-08-21 09:19 UTCGHSA enrichment
  58. 2026-08-21 05:16 UTCVendor advisory
  59. 2026-08-21 05:15 UTCGHSA enrichment
  60. 2026-08-21 00:23 UTCEG score recompute
  61. 2026-08-21 00:23 UTCVendor advisory
  62. 2026-08-21 00:22 UTCGHSA enrichment
  63. 2026-08-20 22:55 UTCEPSS rescore
  64. 2026-08-20 20:18 UTCVendor advisory
  65. 2026-08-20 20:18 UTCGHSA enrichment
  66. 2026-08-20 16:14 UTCVendor advisory
  67. 2026-08-20 16:14 UTCGHSA enrichment
  68. 2026-08-20 11:36 UTCVendor advisory
  69. 2026-08-20 11:36 UTCGHSA enrichment
  70. 2026-08-20 07:29 UTCEG score recompute
  71. 2026-08-20 07:29 UTCVendor advisory
  72. 2026-08-20 07:29 UTCGHSA enrichment
  73. 2026-08-19 17:04 UTCEPSS rescore
  74. 2026-08-19 12:42 UTCVendor advisory
  75. 2026-08-19 12:42 UTCGHSA enrichment

Frequently asked(5)

What is CVE-2026-52993?
CVE-2026-52993 is a critical vulnerability published on June 24, 2026. In the Linux kernel, the following vulnerability has been resolved: tipc: fix double-free in tipcbufappend() tipcmsgvalidate() can potentially reallocate the skb it is validating, freeing the old one. In tipcbufappend(), it was being called with a pointer to a local variable which was a copy of the…
When was CVE-2026-52993 disclosed?
CVE-2026-52993 was first published in the National Vulnerability Database on June 24, 2026, with the most recent update on August 5, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-52993 actively exploited?
CVE-2026-52993 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 69.4% of all scored CVEs.
What is the CVSS score of CVE-2026-52993?
CVE-2026-52993 has a CVSS v4.0 base score of 9.8 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2026-52993?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-52993, 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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