CVE-2026-30871 (GCVE-0-2026-30871)
Vulnerability from cvelistv5
Published
2026-03-19 21:49
Modified
2026-03-25 03:56
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-121 - Stack-based Buffer Overflow
Summary
OpenWrt Project is a Linux operating system targeting embedded devices. In versions prior to 24.10.6 and 25.12.1, the mdns daemon has a Stack-based Buffer Overflow vulnerability in the parse_question function. The issue is triggered by PTR queries for reverse DNS domains (.in-addr.arpa and .ip6.arpa). DNS packets received on UDP port 5353 are expanded by dn_expand into an 8096-byte global buffer (name_buffer), which is then copied via an unbounded strcpy into a fixed 256-byte stack buffer when handling TYPE_PTR queries. The overflow is possible because dn_expand converts non-printable ASCII bytes (e.g., 0x01) into multi-character octal representations (e.g., \001), significantly inflating the expanded name beyond the stack buffer's capacity. A crafted DNS packet can exploit this expansion behavior to overflow the stack buffer, making the vulnerability reachable through normal multicast DNS packet processing. This issue has been fixed in versions 24.10.6 and 25.12.1.
References
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Impacted products
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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