Common Weakness Enumeration
CWE-1290
AllowedIncorrect Decoding of Security Identifiers
Abstraction: Base · Status: Incomplete
The product implements a decoding mechanism to decode certain bus-transaction signals to security identifiers. If the decoding is implemented incorrectly, then untrusted agents can now gain unauthorized access to the asset.
1 vulnerability references this CWE, most recent first.
CVE-2026-55222 (GCVE-0-2026-55222)
Vulnerability from cvelistv5 – Published: 2026-10-23 14:31 – Updated: 2026-10-23 20:57
VLAI
EPSS
VEX
Title
Isar: Unprivileged user ownership of trusted repository GPG public keys storage after bootstrap
Summary
Isar is an integration system for automated root filesystem generation. In versions 0.11 and newer, /etc/apt/trusted.gpg.d is created manually during bootstrap setup to be able to deploy local keys. By that, the directory is owned by the calling user (the one that executes Isar) instead of root. If the calling user's id is identical to one of an unprivileged user inside the image, this user is able to alter existing keys and deploy new ones, silently breaking the apt repo integrity protection. The issue is has no impact on those images that use an immutable rootfs, or if apt is never invoked. Changing only the keys does not trigger an exploit, it's just one step in a chain. An attacker would also have to manipulate a remote repo or intercept non-secure communication with it. This issue has been patched via commit 29e84ed.
Severity
5.1 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-23 20:43 UTC
CWE
- CWE-1290 - Incorrect Decoding of Security Identifiers
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/ilbers/isar/security/advisorie… | x_refsource_CONFIRM |
| https://github.com/ilbers/isar/commit/29e84ed301c… | x_refsource_MISC |
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Mitigation
Architecture and Design
Security identifier decoders must be reviewed for design consistency and common weaknesses.
Mitigation
Implementation
Access and programming flows must be tested in pre-silicon and post-silicon testing in order to check for this weakness.
No CAPEC attack patterns related to this CWE.