TI-2025-21090 Aliases CVE-2025-29458 GHSA-3996-4m5r-mmwf

An issue in MyBB 1.8.38 allows a remote attacker to obtain sensitive information via the…

HIGH 66CWE-918Published 2025-04-17 · Updated 2025-04-23

Key facts

Attack vector: Network
Privileges required: Low
User interaction: None
Attack complexity: Low
Impact type: —
Confidentiality · integrity · availability: High · Low · Low
Fix status: No fix listed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA.

Summary

An issue in MyBB 1.8.38 allows a remote attacker to obtain sensitive information via the Change Avatar function. NOTE: the Supplier disputes this because of the allowed actions of Board administrators and because of SSRF mitigation.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.00442 38th percentileScored 2026-11-07

Public exploit Yes 1 exploit referenceTagged by NVD

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Poc
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
—	—	all versions	—	No fix listed	CNA

— Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:mybb:mybb:1.8.38:::::::*	1.8.38	Vulnerable	mybb

cpe:2.3:a:mybb:mybb:1.8.38:*:*:*:*:*:*:* Versions 1.8.38 Vulnerable ·mybb

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2025-29458
2026-10-03 Alias added: GHSA-3996-4m5r-mmwf

References

Exploit 1

https://www.yuque.com/morysummer/vx41bz/qu7zyyxr84qno64e

Other 1

https://docs.mybb.com/1.8/administration/security/protection/#limit-access-to-private-hosts-and-ip-addresses

TI-2011-04621 myBB 1.6.4 Backdoor Arbitrary Command Execution CVSS 4.0CRITICAL 10.0
TI-2022-08548 Remote code execution in mybb CVSS 3.1HIGH 7.2
TI-2023-21959 MyBB before 1.8.36 allows Code Injection by users with certain high privileges. CVSS 3.1HIGH 7.2
TI-2022-18641 Mail settings' command parameter injection in mybb CVSS 3.1HIGH 7.2
TI-2025-21092 An issue in MyBB 1.8.38 allows a remote attacker to obtain sensitive information via the… CVSS 3.1HIGH 7.6
TI-2025-21091 An issue in MyBB 1.8.38 allows a remote attacker to obtain sensitive information via the… CVSS 3.1HIGH 7.6

See all 139 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences