Penpot: Repeated chunk index causes temporary-storage amplification

published 2026-10-05 34 d ago modified 2026-10-06 33 d ago also EUVD-2026-92779

cvss: 5.3; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 26%
public exploits: 0; none known

Penpot is an open-source design and prototyping platform. Prior to 2.18.0, the chunked media upload RPC validates that a chunk index is in range but neither rejects an already stored index nor replaces its previous object. An authenticated user can repeatedly upload the same valid index, causing each successful request to allocate another temporary object and increasing stored bytes beyond the upload session's declared logical size. Assembly detects the inconsistent chunk count only after allocation. This issue is fixed in version 2.18.0.

Patch / fix

fixed in 1 links 2

kaleidos penpot 2.18.0

github.com/penpot/penpot@0623984 commit
github.com/penpot/penpot/releases/tag/2.18.0 release

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: partial
Assessed: 33 d ago (2026-10-06)

Exploit prediction

0.33% chance of exploitation in the next 30 days, higher than 26% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/penpot/penpot/security/advisories/GHSA-qvq5-c536-pmx8 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	5.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
CNA	4.0	5.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

penpot penpot

Classification

Weakness

CWE-770 Allocation of Resources Without Limits or Throttling

References

Sources

CVE List CVE-2026-105686
NVD CVE-2026-105686

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.

Summary