exec: Force single empty string when argv is empty

Description

In the Linux kernel, the following vulnerability has been resolved: exec: Force single empty string when argv is empty Quoting[1] Ariadne Conill: "In several other operating systems, it is a hard requirement that the second argument to execve(2) be the name of a program, thus prohibiting a scenario where argc < 1. POSIX 2017 also recommends this behaviour, but it is not an explicit requirement[2]: The argument arg0 should point to a filename string that is associated with the process being started by one of the exec functions. ... Interestingly, Michael Kerrisk opened an issue about this in 2008[3], but there was no consensus to support fixing this issue then. Hopefully now that CVE-2021-4034 shows practical exploitative use[4] of this bug in a shellcode, we can reconsider. This issue is being tracked in the KSPP issue tracker[5]." While the initial code searches[6][7] turned up what appeared to be mostly corner case tests, trying to that just reject argv == NULL (or an immediately terminated pointer list) quickly started tripping[8] existing userspace programs. The next best approach is forcing a single empty string into argv and adjusting argc to match. The number of programs depending on argc == 0 seems a smaller set than those calling execve with a NULL argv. Account for the additional stack space in bprm_stack_limits(). Inject an empty string when argc == 0 (and set argc = 1). Warn about the case so userspace has some notice about the change: process './argc0' launched './argc0' with NULL argv: empty string added Additionally WARN() and reject NULL argv usage for kernel threads. [1] https://lore.kernel.org/lkml/[email protected]/ [2] https://pubs.opengroup.org/onlinepubs/9699919799/functions/exec.html [3] https://bugzilla.kernel.org/show_bug.cgi?id=8408 [4] https://www.qualys.com/2022/01/25/cve-2021-4034/pwnkit.txt [5] https://github.com/KSPP/linux/issues/176 [6] https://codesearch.debian.net/search?q=execve%5C+*%5C%28%5B%5E%2C%5D%2B%2C+*NULL&literal=0 [7] https://codesearch.debian.net/search?q=execlp%3F%5Cs*%5C%28%5B%5E%2C%5D%2B%2C%5Cs*NULL&literal=0 [8] https://lore.kernel.org/lkml/20220131144352.GE16385@xsang-OptiPlex-9020/

Scores

EPSS (exploitation in 30 days)

0.30% · top 77% of all CVEs (6 Nov 2026)

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.

Weakness

• CWE-476 (opens in a new tab)All about CWE-476 and its CVEs

Affected products

• Linux · Linux

  • affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < 41f6ea5b9aaa28b740d47ffe995a5013211fdbb0
  • affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < 98e0c7c702894987732776736c99b85ade6fba45
  • affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < b50fb8dbc8b81aaa126387de428f4c42a7c72a73
  • affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < 1fe82bfd9e4ce93399d815ca458b58505191c3e8
  • affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < 27a6f495b63a1804cc71be45911065db7757a98c
  • affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < 1290eb4412aa0f0e9f3434b406dc8e255da85f9e
  • affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < a8054d3fa5deb84b215d6be1b910a978f3cb840d
  • affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < cfbfff8ce5e3d674947581f1eb9af0a1b1807950
  • affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < dcd46d897adb70d63e025f175a00a89797d31a43

• Linux · Linux

  • affected 2.6.12
  • unaffected < 2.6.12
  • unaffected 4.9.317 – ≤ 4.9.*
  • unaffected 4.14.282 – ≤ 4.14.*
  • unaffected 4.19.246 – ≤ 4.19.*
  • unaffected 5.4.197 – ≤ 5.4.*
  • unaffected 5.10.110 – ≤ 5.10.*
  • unaffected 5.15.33 – ≤ 5.15.*
  • unaffected 5.16.19 – ≤ 5.16.*
  • unaffected 5.17.2 – ≤ 5.17.*
  • unaffected 5.18 – ≤ *

References (9)

• https://git.kernel.org/stable/c/41f6ea5b9aaa28b740d47ffe995a5013211fdbb0 (opens in a new tab)
• https://git.kernel.org/stable/c/98e0c7c702894987732776736c99b85ade6fba45 (opens in a new tab)
• https://git.kernel.org/stable/c/b50fb8dbc8b81aaa126387de428f4c42a7c72a73 (opens in a new tab)
• https://git.kernel.org/stable/c/1fe82bfd9e4ce93399d815ca458b58505191c3e8 (opens in a new tab)
• https://git.kernel.org/stable/c/27a6f495b63a1804cc71be45911065db7757a98c (opens in a new tab)
• https://git.kernel.org/stable/c/1290eb4412aa0f0e9f3434b406dc8e255da85f9e (opens in a new tab)
• https://git.kernel.org/stable/c/a8054d3fa5deb84b215d6be1b910a978f3cb840d (opens in a new tab)
• https://git.kernel.org/stable/c/cfbfff8ce5e3d674947581f1eb9af0a1b1807950 (opens in a new tab)
• https://git.kernel.org/stable/c/dcd46d897adb70d63e025f175a00a89797d31a43 (opens in a new tab)

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2022-49264](https://trackcve.app/badge/CVE-2022-49264.svg)](https://trackcve.app/cve/CVE-2022-49264)

Record last updated 5 Aug 2026, 08:54 UTC.