CVE
Zipline stored XSS in HighlightCode component
Affects Zipline versions before 4.5.1, where the HighlightCode component renders raw file content before highlight.js loads. No vendor rating is given, only a CVSS score of 9.3. Fixed in 4.5.1.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- Fixed in 4.5.1
- Who is exposed
- Specific setups only
Do first: Check whether your setup matches what the bug needs. Zipline versions before 4.5.1 (affected versions listed as 4.5.0 and earlier). The bug is hit in the window before highlight.js finishes loading in the HighlightCode component, which renders raw file content.
- Published
- Last modified
- Whether it needs action now or is a reference record, by fixed rules, with why. Last checked is when cve.now last re-read it.What do these mean? →
- Reference
- Last checked
- FIRST's estimate of the chance attackers exploit it in the next 30 days, updated daily.What do these mean? →
- 0.37% · 30th percentile
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 17/100 · provisional
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Specific setups only
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
Zipline before 4.5.1 contains a stored cross-site scripting vulnerability in the HighlightCode component that renders unescaped file content before highlight.js finishes loading. Authenticated attackers can upload text files containing HTML/JavaScript payloads that execute in viewers' browsers, enabling API calls such as account changes on the victim's behalf.
Who should check
Anyone running diced zipline before 4.5.1 where users view uploaded text files, such as file-hosting deployments.
cve.now Index
- Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
- Exposure8/25Specific setups only, reachable over the network
- Reach?/20Unknown. No tracked technology or package matched
- Severity9.3/10CVSS 9.3
- No patch0/5No signal
What would change the score
- Would score about 67 if added to CISA KEV
- Would score about 62 if CISA's SSVC rates exploitation active
- Would score about 24 if CISA's SSVC rates it automatable
What to do
Check whether your setup matches what the bug needs.
Zipline versions before 4.5.1 (affected versions listed as 4.5.0 and earlier). The bug is hit in the window before highlight.js finishes loading in the HighlightCode component, which renders raw file content.Upgrade to a fixed version: 4.5.1.
Check your systems with an agent
Paste this into a coding or ops agent. It checks your systems read-only and reports a table per asset.
Check whether my systems are affected by CVE-2026-126945 (Zipline before 4.5.1 Stored XSS via HighlightCode Component), using the cve.now data below.
Rules: work read-only. Do not run exploit code, proof-of-concept scripts or scanners that send attack payloads, and do not change any configuration, package, image or deployment. Report findings only.
What cve.now has for CVE-2026-126945 (entry last updated 2026-11-13):
Affected:
- diced zipline: fixed in 4.5.1
Fixed versions: 4.5.1.
Conditions (all must be true for the bug to be hit):
- Zipline versions before 4.5.1 (affected versions listed as 4.5.0 and earlier). (source: https://www.vulncheck.com/advisories/zipline-before-4.5.1-stored-xss-via-highlightcode-component)
- The bug is hit in the window before highlight.js finishes loading in the HighlightCode component, which renders raw file content. (source: https://github.com/diced/zipline/security/advisories/GHSA-m649-gvwx-j6qv)
Setup: unknown whether the bug needs a non-default feature or setting. Check the advisory.
Attacker needs: network access, low-privilege login, a user action.
CISA KEV: CVE-2026-126945 is not listed as of cve.now's last read.
This KEV status is for CVE-2026-126945 only. If you also check another CVE, look up its own KEV status; never assume it from this one.
How to check:
- Installed software: check what is actually running, not what a repo declares. Read the version from each host, container image and Kubernetes node (the binary's version output, the OS package database, image layers), and check whether the conditions above hold there. Distribution packages may carry a backported fix under an older version number; confirm against the distribution's own advisory.
Verify against the linked advisories before concluding, and cite the date you read each one:
- https://github.com/diced/zipline/security/advisories/GHSA-m649-gvwx-j6qv
- https://www.vulncheck.com/advisories/zipline-before-4.5.1-stored-xss-via-highlightcode-component
Do not conclude an asset is unaffected unless you checked it and the evidence covers both its version and the conditions above. If you could not check something, mark it unknown and say what is missing.
Report a table with one row per asset and these columns: Asset | Version or build | Status (affected, fixed, not applicable, unknown) | Compensating controls | Exposure (internet-facing, internal, none) | Evidence | Next action.
Entry: https://cve.now/CVE-2026-126945
For follow-up questions, use the cve.now MCP server at https://mcp.cve.now/mcp (no authentication), for example execute with name cve.get and arguments {"id": "CVE-2026-126945"}.Timeline
- CVE published
- First seen by cve.now
- Posted on X by cve.now
Affected versions
- diced zipline
fixed in 4.5.1
Evidence 4
Vendor advisory · 1
Establishes: Affected and fixed versions.
- Advisory
CVE record · 2
Establishes: The identifier and description.
- Record
- Record
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-126945
Is CVE-2026-126945 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
What does this mean?
Zipline's HighlightCode component shows user-supplied file content without HTML escaping or sanitization while highlight.js is still loading. A malicious file can therefore run arbitrary JavaScript in the browser of anyone who views it, make API calls as that user such as account changes, and exfiltrate data.Source: vulncheck.com, github.com
Which versions are affected by CVE-2026-126945?
zipline: before 4.5.1.Source: cve.now feed data
Am I affected, and how do I check?
Zipline versions before 4.5.1, listed as 4.5.0 and earlier. The issue occurs in the brief window before highlight.js finishes loading in the HighlightCode component, so check your installed Zipline version to see whether it falls in that range.Source: vulncheck.com, github.com
How do I fix CVE-2026-126945?
Upgrade Zipline to version 4.5.1 or later, which is the fixed version listed for this vulnerability.Source: vulncheck.com, github.com