CVE-2020-1647Junos OS: SRX Series: Double free vulnerability can lead to DoS or remote code execution due to the processing of a specific HTTP message when ICAP redirect service is enabled
- 9.8CriticalCVSS base score
- 2.6%Exploitation in 30 daysEPSS · top 14% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
On Juniper Networks SRX Series with ICAP (Internet Content Adaptation Protocol) redirect service enabled, a double free vulnerability can lead to a Denial of Service (DoS) or Remote Code Execution (RCE) due to processing of a specific HTTP message. Continued processing of this specific HTTP message may result in an extended Denial of Service (DoS). The offending HTTP message that causes this issue may originate both from the HTTP server or the client. This issue affects Juniper Networks Junos OS on SRX Series: 18.1 versions prior to 18.1R3-S9; 18.2 versions prior to 18.2R3-S3; 18.3 versions prior to 18.3R2-S4, 18.3R3-S1; 18.4 versions prior to 18.4R2-S5, 18.4R3; 19.1 versions prior to 19.1R2; 19.2 versions prior to 19.2R1-S2, 19.2R2; 19.3 versions prior to 19.3R2. This issue does not affect Juniper Networks Junos OS prior to 18.1R1.
Timeline
ID reserved
By juniper
- 9 months later
· 9 months later
Published
- 4 years later
· 4 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| juniperCNA (assigner) | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 2.6% · top 14% of all CVEs (14 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Affected products
- unaffected unspecified – < 18.1R1
- affected 18.1 – < 18.1R3-S9
- affected 18.2 – < 18.2R3-S3
- affected 18.3 – < 18.3R2-S4, 18.3R3-S1
- affected 18.4 – < 18.4R2-S5, 18.4R3
- affected 19.1 – < 19.1R2
- affected 19.2 – < 19.2R1-S2, 19.2R2
- affected 19.3 – < 19.3R2
What to do
Solution: The following software releases have been updated to resolve this specific issue: 18.1R3-S9, 18.2R3-S3, 18.3R2-S4, 18.3R3-S1, 18.4R2-S5, 18.4R3, 19.1R2, 19.2R1-S2, 19.2R2, 19.3R2, 19.4R1, and all subsequent releases.
Workaround: Disable ICAP redirect service otherwise there are no viable workarounds for this issue.
Exploitation: Juniper SIRT is not aware of any malicious exploitation of this vulnerability.
References
References1
- https://kb.juniper.net/JSA11034 (opens in a new tab)x_refsource_CONFIRMx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2020-12512 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2020-1647)Record last updated .