CVE-2026-113783
What it is
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.
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of data tampering, service disruption.
- Exploit odds
- 0.4% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- ReservedThe CVE id was reserved by its CNA
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.4% in the next 30 days (EPSS).
- Severity: 7.4 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.4% · EPSS, next 30 days
- Weakness
- CWE-121
- Record status
- Received
Attack profile CVSS 3.1 · 7.4
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-113783.md and follow it. Check whether this project is affected by CVE-2026-113783. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://github.com/espressif/esp-idf/commit/75f2ff7e0c2d19e113293ec122b701c83d2f6665
- https://github.com/espressif/esp-idf/commit/7ab85eb4dc7d7695960d940badcd62592c365056
- https://github.com/espressif/esp-idf/commit/882843dbf838b0c02e09d46bb6283bda73496b8c
- https://github.com/espressif/esp-idf/commit/98e6e7a08fca391563651a1e751cc45a3b27d18b
- https://github.com/espressif/esp-idf/commit/af7543d00a4d7b489e010a70b59fd3d8022a40f4
- https://github.com/espressif/esp-idf/commit/defaa2f559470acfee5e2e5ea80a79b73424d483
- https://github.com/espressif/esp-idf/security/advisories/GHSA-ch63-jxm5-vmvf
References
- https://github.com/espressif/esp-idf/commit/75f2ff7e0c2d19e113293ec122b701c83d2f6665
- https://github.com/espressif/esp-idf/commit/7ab85eb4dc7d7695960d940badcd62592c365056
- https://github.com/espressif/esp-idf/commit/882843dbf838b0c02e09d46bb6283bda73496b8c
- https://github.com/espressif/esp-idf/commit/98e6e7a08fca391563651a1e751cc45a3b27d18b
- https://github.com/espressif/esp-idf/commit/af7543d00a4d7b489e010a70b59fd3d8022a40f4
- https://github.com/espressif/esp-idf/commit/defaa2f559470acfee5e2e5ea80a79b73424d483
- https://github.com/espressif/esp-idf/security/advisories/GHSA-ch63-jxm5-vmvf