CVE-2026-113783

HIGHCVSS 7.4/10

Last modified

CVE-2026-113783 is a high-severity vulnerability rated 7.4/10 on the CVSS scale. 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.

Description

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.

Metrics

Weakness Enumeration

Affected Software

Source: CNA advisory (CVE.org). NVD analysis pending.

VendorProductVersions
espressifesp-idf>= 5.2.3, <= 5.2.8; >= 5.3.2, < 5.3.7; >= 5.4.0, < 5.4.5; >= 5.5.0, < 5.5.6; >= 6.0.0, < 6.0.3

References

Timeline

Published
Last Modified
Status
Received

Frequently Asked Questions

What is CVE-2026-113783?
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.
How severe is CVE-2026-113783?
CVE-2026-113783 has a CVSS score of 7.4/10 (HIGH severity).
How do I fix CVE-2026-113783?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

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Source: NVD / NIST