CVE-2026-111269

libical through 4.0.6 contains a heap-based out-of-bounds read in icalvalue_decode_ical_string() in src/libical/icalvalue.c when decoding input ending in a backslash. Attackers can supply escaped iCalendar text with a trailing backslash, causing the loop to read past the terminator and crash the application or leak adjacent heap memory.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 4.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/libical/libical
https://github.com/libical/libical/blob/9cfca65c122fa23b9680a28e0c9225a2fd015fc5/src/libical/icalvalue.c#L1608-L1645
https://github.com/libical/libical/commit/d753885ce2de7c105d6b8c405aa7aee1d98ad8de
https://github.com/libical/libical/pull/1455
https://hackmd.io/@haind-pwn/libical-icalvalue-decode-ical-string-oob-read
https://www.vulncheck.com/advisories/libical-through-4.0.6-heap-out-of-bounds-read-via-icalvalue-decode-ical-string
https://hackmd.io/@haind-pwn/libical-icalvalue-decode-ical-string-oob-read

Configurations

No configuration.

History

26 Oct 2026, 15:16

Type	Values Removed	Values Added
References	~~{'url': 'https://hackmd.io/@haind-pwn/cve-2026-111269-libical-icalvalue-decode-ical-string-oob-read', 'source': '134c704f-9b21-4f2e-91b3-4a467353bcc0'}~~
References	~~() https://hackmd.io/@haind-pwn/libical-icalvalue-decode-ical-string-oob-read -~~	() https://hackmd.io/@haind-pwn/libical-icalvalue-decode-ical-string-oob-read -

26 Oct 2026, 14:16

Type	Values Removed	Values Added
References		() https://hackmd.io/@haind-pwn/cve-2026-111269-libical-icalvalue-decode-ical-string-oob-read -

15 Oct 2026, 22:19

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-15 22:19

Updated : 2026-10-26 15:16

NVD link : CVE-2026-111269

Mitre link : CVE-2026-111269

CVE.ORG link : CVE-2026-111269

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

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