asterisk: Uncontrolled Search Path Element
CVE-2026-23741 is a high-severity uncontrolled search path element vulnerability in asterisk, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected asterisk versions: < 23.2.2; < 22.8.2; < 21.12.1, and others listed below. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.21% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of asterisk you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Asterisk | asterisk | < 23.2.2; < 22.8.2; < 21.12.1; < 20.18.2; < 20.7-cert9 | Not stated |
| Sangoma | Certified Asterisk | 18.9 and earlier; 20.7 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 0.0 | None | CNA (github.com) |
| CVSS 3.1 | 8.8 | High | NVD |
Official description
Asterisk is an open source private branch exchange and telephony toolkit. Prior to versions 20.7-cert9, 20.18.2, 21.12.1, 22.8.2, and 23.2.2, the asterisk/contrib/scripts/ast_coredumper runs as root, as noted by the NOTES tag on line 689 of the ast_coredumper file. The script will source the contents of /etc/asterisk/ast_debug_tools.conf, which resides in a folder that is writeable by the asterisk user:group. Due to the /etc/asterisk/ast_debug_tools.conf file following bash semantics and it being loaded; an attacker with write permissions may add or modify the file such that when the root ast_coredumper is run; it would source and thereby execute arbitrary bash code found in the /etc/asterisk/ast_debug_tools.conf. This issue has been patched in versions 20.7-cert9, 20.18.2, 21.12.1, 22.8.2, and 23.2.2.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Uncontrolled Search Path Element
The product uses a fixed or controlled search path to find resources, but one or more locations in that path can be under the control of unintended actors.
How developers prevent this class of flaw
- Hard-code the search path to a set of known-safe values (such as system directories), or only allow them to be specified by the administrator in a configuration file. Do not allow these settings to be modified by an external party. Be careful to avoid related weaknesses such as CWE-426 and CWE-428.
- When invoking other programs, specify those programs using fully-qualified pathnames. While this is an effective approach, code that uses fully-qualified pathnames might not be portable to other systems that do not use the same pathnames. The portability can be improved by locating the full-qualified paths in a centralized, easily-modifiable location within the source code, and having the code refer to these paths.
- Remove or restrict all environment settings before invoking other programs. This includes the PATH environment variable, LD_LIBRARY_PATH, and other settings that identify the location of code libraries, and any application-specific search paths.
More Uncontrolled Search Path Element vulnerabilities (CWE-427)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Other vulnerabilities in asterisk
- 8.2 High severity
- 7.0 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 8.1 High severity
Recent Uncontrolled Search Path Element vulnerabilities
- 7.8 High severity
- 8.4 High severity
- 7.3 High severity
- 8.9 High severity
- 7.1 High severity
- 7.3 High severity
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