Denial of Service via Board Import Zip Bomb

published 2023-11-27 2 y ago modified 2026-09-10 1 mo ago also GHSA-j4c3-3h73-74m9 , EUVD-2023-2981

cvss: 4.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.7%; EPSS 0.7% chance of exploitation in 30 days, percentile 54%
public exploits: 0; none known

Mattermost fails to limit the amount of data extracted from compressed archives during board import in Mattermost Boards allowing an attacker to consume excessive resources, possibly leading to Denial of Service, by importing a board using a specially crafted zip (zip bomb).

Patch / fix

fixed in 3

go github.com/mattermost/mattermost/server/v8 8.1.4, 9.0.2, 9.1.1
go github.com/mattermost/mattermost-server/v6 7.8.13
Mattermost Mattermost 7.8.13, 8.1.4, 9.0.2, 9.1.1

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 23 mo ago (2024-12-02)

Exploit prediction

0.72% chance of exploitation in the next 30 days, higher than 54% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	4.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
GitHub	3.1	4.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

Affected packages

ecosystem	package	affected	fixed in
go	github.com/mattermost/mattermost/server/v8	>=9.1.0, <9.1.1 >=9.0.0, <9.0.2 <8.1.4	9.1.1 9.0.2 8.1.4
go	github.com/mattermost/mattermost-server/v6	<7.8.13	7.8.13

Affected products

Mattermost Mattermost

Classification

Weakness

CWE-400 Uncontrolled Resource Consumption

References

mattermost.com /security-updates
web, vendor-advisory
nvd.nist.gov /vuln/detail/CVE-2023-48268
advisory
github.com /mattermost/mattermost
package

Sources

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.

Summary