Pyspark: Apache Spark History Server allows stored cross-site scripting through unescaped application names
Affects pysparkSource GCVE Database
Not known to be exploited · CVSS 6.1 Medium : upgrade to 3.5.8 when convenient.
Data as of 26 Oct 2026, 12:55 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 35% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 3.5.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 2 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade pyspark and org.apache.spark:spark-core_2.12 and org.apache.spark:spark-core_2.13 to 3.5.8.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| PyPIpyspark | Affected
| Fixed in
|
| Mavenorg.apache.spark:spark-core_2.12 | Affected
| Fixed in
|
| Mavenorg.apache.spark:spark-core_2.13 | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
There is a lack of XSS escaping in the Spark History Server prior to 3.5.8 which allows a malicious Spark job to generate arbitrary unescaped frontend code which could lead to a minimal privilege escalation in browser. Users are encouraged to upgrade to Spark 3.5.8 or later. This CVE is marked as "low" since the path to exploit requires both relatively high permissions (ability to launch a Spark job) and requires tricking a user with higher permissions to log in and visit the Spark history web page. Users are encouraged to upgrade their Spark history servers to Spark 3.5.8 or later.
References
- nvd.nist.gov/vuln/detail/CVE-2026-32773 (opens in a new tab)
- github.com/apache/spark/pull/52851 (opens in a new tab)
- github.com/apache/spark/commit/3c83c2c6a22fe384280b99bb753b14800b7e27e1 (opens in a new tab)
- github.com/apache/spark/commit/e739b7d349dbd41b78d49bc8086cab63db057e14 (opens in a new tab)
- github.com/apache/spark (opens in a new tab)
- github.com/pypa/advisory-database/tree/main/vulns/pyspark/PYSEC-2026-3966.yaml (opens in a new tab)
- issues.apache.org/jira/browse/SPARK-53747 (opens in a new tab)
- lists.apache.org/thread/k36prh3oxl1z6ov7w8rpmfnt07hmzw3v (opens in a new tab)
- openwall.com/lists/oss-security/2026/09/01/4 (opens in a new tab)