Low Cryptography exploit reference

CVE-2026-7845 — chatchat-space Langchain-Chatchat Vision Chat Paste Image dialogue.py PIL.Image.tobytes weak hash

A flaw has been found in chatchat-space Langchain-Chatchat up to 0.3.1.3. This issue affects the function PIL.Image.tobytes of the file libs/chatchat-server/chatchat/webui_pages/dialogue/dialogue.py of the component Vision Chat Paste Image Handler. This manipulation of the argument paste_image.image_data causes use of weak hash. The attacker needs to be present on the local network. The attack is considered to have high complexity. The exploitability is assessed as difficult. The exploit has been published and may be used. The project was informed of the problem early through an issue report but has not responded yet.

Published May 5, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: VulDB

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.2% (30-day exploitation probability)+1
CISA SSVC: exploitation "poc"+5

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.2%

ahead of 9% of scored CVEs · Oct 14, 2026

Affects

Chatchat-space

Langchain-Chatchat

CVSS base

2.6

Low · 2 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation

Proof of concept

none · proof-of-concept · active

Automatable

can an attacker script the kill-chain steps

Technical impact

Partial

partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Chatchat-space Langchain-Chatchat).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes matching the vulnerability class (cryptography), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Chatchat-space	Langchain-Chatchat	version 0.3.1.0version 0.3.1.1version 0.3.1.2version 0.3.1.3	Vulnerable	CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector

Adjacent

Attack complexity

High

Privileges required

Low

User interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

Low

Availability

None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Scored by
2.1	CVSS 4.0	Low	—	—	VulDB via CVE Program (cve.org) e CISA ADP
1.2	CVSS 4.0	Low	—	—	cna@vuldb.com via NIST National Vulnerability Database
2.6	CVSS 3.1	Low	1.2	1.4	cna@vuldb.com via NIST National Vulnerability Database
2.6	CVSS 3.1	Low	—	—	VulDB via CVE Program (cve.org) e CISA ADP
2.6	CVSS 3.0	Low	—	—	VulDB via CVE Program (cve.org) e CISA ADP
1.4	CVSS 2.0	Low	2.5	2.9	cna@vuldb.com via NIST National Vulnerability Database
1.4	CVSS 2.0	Low	—	—	VulDB via CVE Program (cve.org) e CISA ADP

CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N (score shown at the top: cna@vuldb.com)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-327 · Use of a Broken or Risky Cryptographic Algorithm

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.20%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Check TLS negotiations and unexpected certificates in the component’s traffic.

network IDS/IPS

Timeline

What happened to this CVE, newest first.

2026
Affected products added · chatchat-space/langchain-chatchat
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
SSVC assessment updated
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 13, 2026
CVSS changed · 2.6
Oct 13, 2026 · NIST National Vulnerability Database
Source status changed · → Deferred
Oct 13, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 13, 2026 · NIST National Vulnerability Database
CVE published
May 5, 2026 · VulDB

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

6 on the record

github.com/3em0/cve_repo/blob/main/Langchain-Chatchat/Vuln-1-tobytes-Hash-Collis
exploit, NIST National Vulnerability Database
vuldb.com/vuln/361124
vdb-entry, technical-description, NIST National Vulnerability Database
github.com/chatchat-space/Langchain-Chatchat/
product, NIST National Vulnerability Database
vuldb.com/submit/807794
third-party-advisory, NIST National Vulnerability Database
github.com/chatchat-space/Langchain-Chatchat/issues/5462
issue-tracking, NIST National Vulnerability Database
vuldb.com/vuln/361124/cti
signature, permissions-required, NIST National Vulnerability Database

Elsewhere on this site

Chatchat-space
every CVE for this vendor

Cryptography
same class

CWE-327
other pages naming this weakness

Related CVEs (same products)

Low CVE-2026-7847 chatchat-space Langchain-Chatchat Uploaded File openai_routes.py _get_file_id random values May 5, 2026
Low CVE-2026-7846 chatchat-space Langchain-Chatchat OpenAI-Compatible File Upload API openai_routes.py files toctou May 5, 2026
Medium CVE-2026-7844 chatchat-space Langchain-Chatchat Compatible File Service openai_routes.py delete_file missing authentication May 5, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No fixed version, patch or mitigation documented.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-7845 is "chatchat-space Langchain-Chatchat Vision Chat Paste Image dialogue.py PIL.Image.tobytes weak hash", rated Low. It affects Langchain-Chatchat (Chatchat-space); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 2.6 describes technical severity. EPSS 0.20% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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