CVE intelligence and bounded remediation
CVE-2022-45939 — Gnu Emacs security vulnerability
GNU Emacs through 28.2 allows attackers to execute commands via shell metacharacters in the name of a source-code file, because lib-src/etags.c uses the system C library function in its implementation of the ctags program. For example, a victim may use the "ctags *" command (suggested in the ctags documentation) in a situation where the current working directory has contents that depend on untrusted input.
- Severity
- High
- CVSS
- 7.8 (3.1)
- Published
- 2022-11-28
- CISA KEV
- Not currently listed
- Ecosystem
- software/application
- Weaknesses
- CWE-78
Affected products
- gnu / emacs
- debian / debian_linux / 10.0
- debian / debian_linux / 11.0
- fedoraproject / fedora / 36
- fedoraproject / fedora / 37
Matched remediation archetype
Command, code, expression, and template injection
This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.
Check exposure
- Trace untrusted values to process execution, interpreters, evaluators, template engines, dynamic imports, and administrative scripting features.
- Determine whether the affected path is reachable across each trust boundary and which service account or host privilege it inherits.
- Review configuration for optional execution features, unsafe compatibility modes, and shell invocation.
Remediate safely
- Replace string-built commands or evaluated code with fixed operations and structured argument APIs that do not invoke a shell.
- Use strict allowlists for operation identifiers and reject unexpected input before it reaches any interpreter.
- Update the affected component and add inert regression tests covering metacharacters, encoding variants, and alternate request paths.
Authoritative sources
Complete CVE record and remediation plan
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