CVE-2026-107611Out-of-bounds read in TightVNC Viewer ZRLE palette decoding
Updated under an hour ago ()
Does this affect you?
It affects GlavSoft TightVNC. Add what you run to find out whether that includes you.
EPSS puts the chance of exploitation in the next 30 days at 0.24%, higher than 13% of scored CVEs.
Do this next
Free account, 1 product
An out-of-bounds read vulnerability in the ZRLE decoder of GlavSoft TightVNC Viewer for Windows before 2.8.88 allows a malicious or compromised VNC server to read heap memory beyond the palette allocation and crash the viewer by sending ZRLE-encoded tiles whose palette indices exceed the declared palette size. readPaletteRleTile() and readPackedPaletteTile() use the attacker-supplied index to look up colours without validating it against the palette size; out-of-bounds heap data is copied into the framebuffer (garbled display) or the read faults, terminating the viewer.
- CVSS
- 7.1 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H
- Weakness (CWE)
- CWE-125
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- 0.24% (percentile 13)
- Assigned by
- securin
- NVD analysis
- Awaiting Analysis
- Record last updated
- Oct 8, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
GlavSoft TightVNC glavsoft:tightvnc (from the name) | before 2.8.88 | CNA record |
References
- https://sourceforge.net/p/vnc-tight/bugs/1657/issue-tracking
- https://www.tightvnc.com/whatsnew.phprelease-notes, patch
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.