CVE-2026-113783 json
ESP-IDF: Stack-based memory corruption in lwIP DNS/SNTP handling for multi-IP DNS responses
published 5d ago modified 9h ago also EUVD-2026-117052
- cvss
- 7.4
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 28%
- public exploits
- 0
- none known
Summary
ESP-IDF is the Espressif Internet of Things (IOT) Development Framework. From 5.2.3 until 5.3.7, 5.4.5, 5.5.6, and 6.0.3, the lwIP DNS resolver's cached-lookup path in dns_lookup() in dns.c copies every cached address into a caller-provided single ip_addr_t output buffer without a length parameter or bounds check. When CONFIG_LWIP_DNS_MAX_HOST_IP is greater than 1 and a cached hostname has multiple A or AAAA records, a subsequent lookup through dns_gethostbyname() or dns_gethostbyname_addrtype() writes beyond the single-element buffer into adjacent stack memory. A network-positioned attacker who influences DNS responses can cause a reboot through stack-canary corruption or, without stack protection, overwrite stack variables with attacker-controlled address bytes and potentially redirect control flow. This issue is fixed in versions 5.5.6 and 6.0.3 and is scheduled to be fixed in versions 5.3.7 and 5.4.5. No fixed release is available for the end-of-life 5.2 line.
Patch / fix
Is CVE-2026-113783 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 9h ago
Exploit prediction
0.35% chance of exploitation in the next 30 days, higher than 28% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.4 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H |
Affected products
- espressif esp-idf
Classification
- Weakness
-
- CWE-121 Stack-based Buffer Overflow
References
- github.com /espressif/esp-idf/commit/75f2ff7e0c2d19e113293ec122b701c83d2f6665
- github.com /espressif/esp-idf/commit/7ab85eb4dc7d7695960d940badcd62592c365056
- github.com /espressif/esp-idf/commit/882843dbf838b0c02e09d46bb6283bda73496b8c
- github.com /espressif/esp-idf/commit/98e6e7a08fca391563651a1e751cc45a3b27d18b
- github.com /espressif/esp-idf/commit/af7543d00a4d7b489e010a70b59fd3d8022a40f4
- github.com /espressif/esp-idf/commit/defaa2f559470acfee5e2e5ea80a79b73424d483
- github.com /espressif/esp-idf/security/advisories/GHSA-ch63-jxm5-vmvf
Sources
- CVE List CVE-2026-113783
- NVD CVE-2026-113783
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