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FKIE_CVE-2026-80848

Vulnerability from fkie_nvd - Published: 2026-09-04 16:18 - Updated: 2026-09-04 16:18
Severity
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.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/24efebecf415ba264adba0f0491cec436463a14f
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/29121c5e6591da527e8e36ddac7120dc527f574d
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/4b31a875693c480c611519faca46216514e3e052
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/4bc0dfa28dca6fc0084203732695968049c44072
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/54b41ad14da9a981131ab6e4d3f79321a503ea5d
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/deb232e884877bf10b4ce2580909eedec986c284
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/eb3bbf29c723fe75c0eb92be14f0ec92971fe272
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/ed5d9102190c45fc70121c036b0626b740040b75
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/ff8dd7a932f34409a56e1b91a1219340f17457e9
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/xfrm/espintcp.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "29121c5e6591da527e8e36ddac7120dc527f574d",
              "status": "affected",
              "version": "e27cca96cd68fa2c6814c90f9a1cfd36bb68c593",
              "versionType": "git"
            },
            {
              "lessThan": "ed5d9102190c45fc70121c036b0626b740040b75",
              "status": "affected",
              "version": "e27cca96cd68fa2c6814c90f9a1cfd36bb68c593",
              "versionType": "git"
            },
            {
              "lessThan": "4bc0dfa28dca6fc0084203732695968049c44072",
              "status": "affected",
              "version": "e27cca96cd68fa2c6814c90f9a1cfd36bb68c593",
              "versionType": "git"
            },
            {
              "lessThan": "ff8dd7a932f34409a56e1b91a1219340f17457e9",
              "status": "affected",
              "version": "e27cca96cd68fa2c6814c90f9a1cfd36bb68c593",
              "versionType": "git"
            },
            {
              "lessThan": "4b31a875693c480c611519faca46216514e3e052",
              "status": "affected",
              "version": "e27cca96cd68fa2c6814c90f9a1cfd36bb68c593",
              "versionType": "git"
            },
            {
              "lessThan": "24efebecf415ba264adba0f0491cec436463a14f",
              "status": "affected",
              "version": "e27cca96cd68fa2c6814c90f9a1cfd36bb68c593",
              "versionType": "git"
            },
            {
              "lessThan": "eb3bbf29c723fe75c0eb92be14f0ec92971fe272",
              "status": "affected",
              "version": "e27cca96cd68fa2c6814c90f9a1cfd36bb68c593",
              "versionType": "git"
            },
            {
              "lessThan": "54b41ad14da9a981131ab6e4d3f79321a503ea5d",
              "status": "affected",
              "version": "e27cca96cd68fa2c6814c90f9a1cfd36bb68c593",
              "versionType": "git"
            },
            {
              "lessThan": "deb232e884877bf10b4ce2580909eedec986c284",
              "status": "affected",
              "version": "e27cca96cd68fa2c6814c90f9a1cfd36bb68c593",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/xfrm/espintcp.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.6"
            },
            {
              "lessThan": "5.6",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.269",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.220",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.187",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.156",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.108",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.49",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.13",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.3",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "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."
    }
  ],
  "id": "CVE-2026-80848",
  "lastModified": "2026-09-04T16:18:13.540",
  "metrics": {},
  "published": "2026-09-04T16:18:13.540",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "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"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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