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CVE-2026-80848 (GCVE-0-2026-80848)

Vulnerability from cvelistv5 – Published: 2026-09-04 15:54 – Updated: 2026-09-04 15:54
VLAI
Title
xfrm: espintcp: fix UAF during close
Summary
In the Linux kernel, the following vulnerability has been resolved: xfrm: espintcp: fix UAF during close ZDI reported and analyzed a race condition during close for espintcp sockets: espintcp_close() frees emsg->skb via kfree_skb() without holding any socket lock. Concurrently, the xfrm_trans_reinject work queue invokes esp_output_tcp_finish() -> espintcp_push_skb() -> espintcp_push_msgs() -> skb_send_sock_locked(), which reads the same skb as a data source. Fix this by adding a synchronize_rcu() call after resetting sk_prot, since esp_output_tcp_finish() runs under RCU and won't use a socket with sk_prot == &tcp_prot. Simply taking the socket lock in espintcp_close() could lead to leaks, if esp_output_tcp_finish() re-adds an skb in the slot we just freed. After this, the existing barrier() is no longer needed.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 , < 29121c5e6591da527e8e36ddac7120dc527f574d (git)
Affected: e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 , < ed5d9102190c45fc70121c036b0626b740040b75 (git)
Affected: e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 , < 4bc0dfa28dca6fc0084203732695968049c44072 (git)
Affected: e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 , < ff8dd7a932f34409a56e1b91a1219340f17457e9 (git)
Affected: e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 , < 4b31a875693c480c611519faca46216514e3e052 (git)
Affected: e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 , < 24efebecf415ba264adba0f0491cec436463a14f (git)
Affected: e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 , < eb3bbf29c723fe75c0eb92be14f0ec92971fe272 (git)
Affected: e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 , < 54b41ad14da9a981131ab6e4d3f79321a503ea5d (git)
Affected: e27cca96cd68fa2c6814c90f9a1cfd36bb68c593 , < deb232e884877bf10b4ce2580909eedec986c284 (git)
guessed Create a notification for this product.
Linux Linux Affected: 5.6
Unaffected: 0 , < 5.6 (semver)
Unaffected: 5.10.269 , ≤ 5.10.* (semver)
Unaffected: 5.15.220 , ≤ 5.15.* (semver)
Unaffected: 6.1.187 , ≤ 6.1.* (semver)
Unaffected: 6.6.156 , ≤ 6.6.* (semver)
Unaffected: 6.12.108 , ≤ 6.12.* (semver)
Unaffected: 6.18.49 , ≤ 6.18.* (semver)
Unaffected: 7.1.13 , ≤ 7.1.* (semver)
Unaffected: 7.2.3 , ≤ 7.2.* (semver)
Unaffected: 7.3-rc1 , ≤ * (original_commit_for_fix)
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          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: espintcp: fix UAF during close\n\nZDI reported and analyzed a race condition during close for espintcp\nsockets:\n\n    espintcp_close() frees emsg-\u003eskb via kfree_skb() without holding\n    any socket lock. Concurrently, the xfrm_trans_reinject work queue\n    invokes esp_output_tcp_finish() -\u003e espintcp_push_skb() -\u003e\n    espintcp_push_msgs() -\u003e skb_send_sock_locked(), which reads the\n    same skb as a data source.\n\nFix this by adding a synchronize_rcu() call after resetting sk_prot,\nsince esp_output_tcp_finish() runs under RCU and won\u0027t use a socket\nwith sk_prot == \u0026tcp_prot.  Simply taking the socket lock in\nespintcp_close() could lead to leaks, if esp_output_tcp_finish()\nre-adds an skb in the slot we just freed. After this, the existing\nbarrier() is no longer needed."
        }
      ],
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        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
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        },
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          "url": "https://git.kernel.org/stable/c/deb232e884877bf10b4ce2580909eedec986c284"
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      "title": "xfrm: espintcp: fix UAF during close",
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    "assignerShortName": "Linux",
    "cveId": "CVE-2026-80848",
    "datePublished": "2026-09-04T15:54:58.427Z",
    "dateReserved": "2026-08-26T14:34:25.797Z",
    "dateUpdated": "2026-09-04T15:54:58.427Z",
    "state": "PUBLISHED"
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      "title": "xfrm: espintcp: fix UAF during close",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-80848.json",
      "version": "1"
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Simply taking the socket lock in\\nespintcp_close() could lead to leaks, if esp_output_tcp_finish()\\nre-adds an skb in the slot we just freed. After this, the existing\\nbarrier() is no longer needed.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"net/xfrm/espintcp.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"e27cca96cd68fa2c6814c90f9a1cfd36bb68c593\",\"lessThan\":\"29121c5e6591da527e8e36ddac7120dc527f574d\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"e27cca96cd68fa2c6814c90f9a1cfd36bb68c593\",\"lessThan\":\"ed5d9102190c45fc70121c036b0626b740040b75\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"e27cca96cd68fa2c6814c90f9a1cfd36bb68c593\",\"lessThan\":\"4bc0dfa28dca6fc0084203732695968049c44072\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"e27cca96cd68fa2c6814c90f9a1cfd36bb68c593\",\"lessThan\":\"ff8dd7a932f34409a56e1b91a1219340f17457e9\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"e27cca96cd68fa2c6814c90f9a1cfd36bb68c593\",\"lessThan\":\"4b31a875693c480c611519faca46216514e3e052\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"e27cca96cd68fa2c6814c90f9a1cfd36bb68c593\",\"lessThan\":\"24efebecf415ba264adba0f0491cec436463a14f\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"e27cca96cd68fa2c6814c90f9a1cfd36bb68c593\",\"lessThan\":\"eb3bbf29c723fe75c0eb92be14f0ec92971fe272\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"e27cca96cd68fa2c6814c90f9a1cfd36bb68c593\",\"lessThan\":\"54b41ad14da9a981131ab6e4d3f79321a503ea5d\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"e27cca96cd68fa2c6814c90f9a1cfd36bb68c593\",\"lessThan\":\"deb232e884877bf10b4ce2580909eedec986c284\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"net/xfrm/espintcp.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"5.6\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"5.6\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.10.269\",\"lessThanOrEqual\":\"5.10.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.220\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.187\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.156\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.108\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.49\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1.13\",\"lessThanOrEqual\":\"7.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.2.3\",\"lessThanOrEqual\":\"7.2.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.3-rc1\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/24efebecf415ba264adba0f0491cec436463a14f\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/29121c5e6591da527e8e36ddac7120dc527f574d\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/4b31a875693c480c611519faca46216514e3e052\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/4bc0dfa28dca6fc0084203732695968049c44072\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/54b41ad14da9a981131ab6e4d3f79321a503ea5d\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/deb232e884877bf10b4ce2580909eedec986c284\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/eb3bbf29c723fe75c0eb92be14f0ec92971fe272\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/ed5d9102190c45fc70121c036b0626b740040b75\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/ff8dd7a932f34409a56e1b91a1219340f17457e9\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-09-06T16:55:17Z",
      "cve": "CVE-2026-80848",
      "id": "CVE-2026-80848",
      "initial_release_date": "2026-09-05T00:26:15Z",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-80848",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-80848.json",
      "version": "3"
    }
  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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