{"id":"CVE-2025-39847","title":"ppp: fix memory leak in pad_compress_skb","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nppp: fix memory leak in pad_compress_skb\n\nIf alloc_skb() fails in pad_compress_skb(), it returns NULL without\nreleasing the old skb. The caller does:\n\n    skb = pad_com…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= b3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 9ca6a040f76c0b149293e430dabab446f3fc8ab7","Linux >= b3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 87a35a36742df328d0badf4fbc2e56061c15846c","Linux >= b3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 0b21e9cd4559102da798bdcba453b64ecd7be7ee","Linux >= b3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 1d8b354eafb8876d8bdb1bef69c7d2438aacfbe8","Linux >= b3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 85c1c86a67e09143aa464e9bf09c397816772348","Linux >= b3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 631fc8ab5beb9e0ec8651fb9875b9a968e7b4ae4","Linux >= b3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 33a5bac5f14772730d2caf632ae97b6c2ee95044","Linux >= b3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 4844123fe0b853a4982c02666cb3fd863d701d50","Linux 2.6.15"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-05T21:12:34.406594Z"},"published":"2025-09-19","updated":"2026-11-05","sourceUpdated":"2026-11-05T21:13:00.053Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2025-39847","references":[{"url":"https://git.kernel.org/stable/c/9ca6a040f76c0b149293e430dabab446f3fc8ab7"},{"url":"https://git.kernel.org/stable/c/87a35a36742df328d0badf4fbc2e56061c15846c"},{"url":"https://git.kernel.org/stable/c/0b21e9cd4559102da798bdcba453b64ecd7be7ee"},{"url":"https://git.kernel.org/stable/c/1d8b354eafb8876d8bdb1bef69c7d2438aacfbe8"},{"url":"https://git.kernel.org/stable/c/85c1c86a67e09143aa464e9bf09c397816772348"},{"url":"https://git.kernel.org/stable/c/631fc8ab5beb9e0ec8651fb9875b9a968e7b4ae4"},{"url":"https://git.kernel.org/stable/c/33a5bac5f14772730d2caf632ae97b6c2ee95044"},{"url":"https://git.kernel.org/stable/c/4844123fe0b853a4982c02666cb3fd863d701d50"}],"tags":["cve.org"],"epss":0.00164,"epssPercentile":0.05619,"ingestedAt":"2026-11-05T22:38:32.034Z","slug":"CVE-2025-39847","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nppp: fix memory leak in pad_compress_skb\n\nIf alloc_skb() fails in pad_compress_skb(), it returns NULL without\nreleasing the old skb. The caller does:\n\n    skb = pad_compress_skb(ppp, skb);\n    if (!skb)\n        goto drop;\n\ndrop:\n    kfree_skb(skb);\n\nWhen pad_compress_skb() returns NULL, the reference to the old skb is\nlost and kfree_skb(skb) ends up doing nothing, leading to a memory leak.\n\nAlign pad_compress_skb() semantics with realloc(): only free the old\nskb if allocation and compression succeed.  At the call site, use the\nnew_skb variable so the original skb is not lost when pad_compress_skb()\nfails.\n\n## Affected\n\n- `Linux >= b3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 9ca6a040f76c0b149293e430dabab446f3fc8ab7`\n- `Linux >= b3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 87a35a36742df328d0badf4fbc2e56061c15846c`\n- `Linux >= b3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 0b21e9cd4559102da798bdcba453b64ecd7be7ee`\n- `Linux >= b3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 1d8b354eafb8876d8bdb1bef69c7d2438aacfbe8`\n- `Linux >= b3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 85c1c86a67e09143aa464e9bf09c397816772348`\n- `Linux >= b3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 631fc8ab5beb9e0ec8651fb9875b9a968e7b4ae4`\n- `Linux >= b3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 33a5bac5f14772730d2caf632ae97b6c2ee95044`\n- `Linux >= b3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 4844123fe0b853a4982c02666cb3fd863d701d50`\n- `Linux 2.6.15`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}