atjiu pybbs CommentApiController.java create cross site scripting

published 2026-03-20 7 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-13758

cvss: 3.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 20%
public exploits: 0; none known

A security flaw has been discovered in atjiu pybbs 6.0.0. This impacts the function create of the file src/main/java/co/yiiu/pybbs/controller/api/CommentApiController.java. The manipulation results in cross site scripting. It is possible to launch the attack remotely. The exploit has been released to the public and may be used for attacks.

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 7 mo ago (2026-03-20)

Exploit prediction

0.28% chance of exploitation in the next 30 days, higher than 20% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

fx4tqqfvdw4.feishu.cn https://fx4tqqfvdw4.feishu.cn/docx/PN3YdPBpsowyU1xTV1VcVTm9nzg?from=from_copylink referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	5.1	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P
CNA	3.1	3.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N/E:P/RL:X/RC:R
CNA	3.0	3.5	CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N/E:P/RL:X/RC:R
CNA	2.0	4.0	AV:N/AC:L/Au:S/C:N/I:P/A:N/E:POC/RL:ND/RC:UR
CNA	4.0	2.0	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/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
CNA	3.1	3.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
CNA	2.0	4.0	AV:N/AC:L/Au:S/C:N/I:P/A:N

Affected products

atjiu pybbs

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation
CWE-94 Improper Control of Generation of Code

References

fx4tqqfvdw4.feishu.cn /docx/PN3YdPBpsowyU1xTV1VcVTm9nzg?from=from_copylink
exploit
vuldb.com /?id.352021
vdb-entry, technical-description
vuldb.com /?ctiid.352021
signature, permissions-required
vuldb.com /?submit.773780
third-party-advisory

Sources

CVE List CVE-2026-4495
NVD CVE-2026-4495

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