CVE-2026-48111: mcmilk 7-Zip · Out-of-bounds Read
Affects mcmilk 7-ZipSource CVE Database V5
Not known to be exploited · CVSS 4.3 Medium : upgrade to 26.01 when convenient.
Data as of 30 Oct 2026, 06:59 UTC
- EPSS
- 2.1% chance of exploitation in 30 days – higher than 82% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 26.01
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:LExploitation evidence
Disclosed: evidence found.
CVE published 5 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Upgrade 7-Zip and mcmilk/7-zip to 26.01.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| mcmilk7-Zip | Affected
| Fixed in
|
GitHubmcmilk/7-zippkg:github/mcmilk/7-zipOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade to 7-Zip version 26.01 or later, where this vulnerability is fixed. No other official remediation or temporary fix is documented. Users should apply the update to prevent potential denial of service or information disclosure.
Description
7-Zip is a file archiver with a high compression ratio. Versions 9.21 through 26.00 contain an off-by-one out-of-bounds read vulnerability in the ParseDepedencyExpression function of the UEFI firmware image parser(CPP/7zip/Archive/UefiHandler.cpp). The function validates an attacker-controlled opcode byte using > instead of >= against the element count of the 10-entry kExpressionCommands static array, allowing an opcode value of 10 to read one pointer slot (8 bytes on x64) past the end of the array in .rodata. The out-of-bounds value is then dereferenced as a const char * and passed through strlen and memcpy into the archive's Characts property, which may cause either a denial of service (access violation when the adjacent bytes do not form a valid readable pointer) or a minor information disclosure of an adjacent .rdata string literal into archive metadata. The vulnerability is reached automatically during IInArchive::Open() via the call path OpenFv/OpenCapsule → ParseVolume → ParseSections when processing a SECTION_DXE_DEPEX (0x13) or SECTION_PEI_DEPEX (0x1B) section whose first body byte is 0x0A, and the UEFI handler is enabled by default in stock 7z.dll with signature-based detection for both UEFIc and UEFIf formats. The outcome (crash vs. silent leak) is deterministic per build but linker-layout dependent, with no write primitive and no disclosure of heap data, secrets, or ASLR base addresses. Version 26.01 fixes the issue.