CVE-2023-36846
A Missing Authentication for Critical Function vulnerability in Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause limited impact to the file system integrity. With a specific request to user.php that doesn't require authentication an attacker is able to upload arbitrary files via J-Web, leading to a loss of integrity for a certain part of the file system, which may allow chaining to other vulnerabilities. This issue affects Juniper Networks Junos OS on SRX Series: * All versions prior to 20.4R3-S8; * 21.1 versions 21.1R1 and later; * 21.2 versions prior to 21.2R3-S6; * 21.3 versions prior to 21.3R3-S5; * 21.4 versions prior to 21.4R3-S5; * 22.1 versions prior to 22.1R3-S3; * 22.2 versions prior to 22.2R3-S2; * 22.3 versions prior to 22.3R2-S2, 22.3R3; * 22.4 versions prior to 22.4R2-S1, 22.4R3.
- CVSS
- 5.3Mediumscored by the publisher (CNA)
- Exploited in the wild
- Yes, in CISA KEV since 13 Nov 2023CISA deadline for US federal agencies: 17 Nov 2023unvetted proof-of-concept code on github
- EPSS
- 93.5%chance of exploitation in the next 30 daystop 0.2% of scored CVEsFIRST score of 11 Nov 2026
- Fix
- Patch availablesee the advisories in the references
- Published
- 17 Aug 2023analysed here 12 Nov 2026
Do first. Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. (CISA's required action for this KEV entry)
Summary
Triage
The summary, impact and action text on this page are written by our AI analysis pipeline, or taken from the NVD description when a CVE was imported from NVD. They are not the vendor's wording: check them against the sources. A longer AI executive summary and technical analysis are generated for signed-in accounts on the Max plan.
Affected products
| Product | Affected versions | Vendor says fixed in |
|---|---|---|
| Juniper Networks Junos OS | < 20.4R3-S8>= 21.1 and < 21.1*>= 21.2 and < 21.2R3-S6>= 21.3 and < 21.3R3-S5>= 21.4 and < 21.4R3-S5>= 22.1 and < 22.1R3-S3>= 22.2 and < 22.2R3-S2>= 22.3 and < 22.3R2-S2, 22.3R3>= 22.4 and < 22.4R2-S1, 22.4R3Vendor says fixed in: not stated |
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.
Products named in our analysis
- juniper:junos
Fix and mitigation
WAF and other mitigations
Can a WAF block it? Partly. The attacker sends a specific HTTP request to user.php to upload arbitrary files without authentication, which is unusual and can be detected by matching unauthenticated file upload attempts to this endpoint. A WAF rule can match file upload requests to user.php without authentication. No tracked WAF vendor has published a rule for this CVE yet, so you would write it yourself.
What a custom rule would match: file upload requests to user.php without authentication
Also consider: patch · custom WAF rule
Based on an AI reading of the CVE description, and no vendor rule found yet. We check Cloudflare, AWS, Google Cloud Armor and Azure; for Akamai, Imperva, Fastly, F5, ask your vendor.
Remediation steps (AI-written)
Step-by-step remediation is generated for accounts on the Max plan, for CVEs that match a technology in their stack. Add this technology to your stack to see the fix checklist.
Exploitation evidence
- CISA KEV catalog
- Listed since 13 Nov 2023.
- CISA due date
- 17 Nov 2023, the remediation deadline for US federal agencies
- CISA required action
- Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
- Public exploit code
- Unvetted proof-of-concept code on GitHub: 1 GitHub proof of concept
- CISA SSVC
- exploitation active, automatable yes, technical impact totalAssessed by CISA 15 Nov 2023 (SSVC 2.0.3). Exploitation is none, poc (public proof of concept) or active.
GitHub proofs of concept
- Chocapikk/CVE-2023-368465 stars
Listed so you can judge urgency, not as a recommendation to run anything. GitHub “proofs of concept” are unvetted: some are fake or carry malware. Exploit-DB marks the entries its staff verified.
Timeline
- 17 Aug 2023Published
- 29 Aug 2023First proof-of-concept repository on GitHub (unvetted)11 days later
- 13 Nov 2023Added to CISA KEV (exploited in the wild)76 days (about 3 months) later
- 15 Nov 2023CISA SSVC assessment: exploitation active3 days later
- 17 Nov 2023CISA remediation due date (US federal agencies)1 day later
- 21 Oct 2025CVE record last updated705 days (about 2 years) later
- 12 Nov 2026Analysed by vulneraibility.com387 days (about 1 year) later
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
| Metric | Value | What it means |
|---|---|---|
| Attack vector | NetworkReachable over the internet or any routable network. | Reachable over the internet or any routable network. |
| Attack complexity | LowRepeatable attack, no special conditions. | Repeatable attack, no special conditions. |
| Privileges required | NoneThe attacker needs no prior access. | The attacker needs no prior access. |
| User interaction | NoneNo victim action needed. | No victim action needed. |
| Scope | UnchangedImpact stays within the vulnerable component. | Impact stays within the vulnerable component. |
| Confidentiality | NoneNo data disclosure. | No data disclosure. |
| Integrity | LowLimited modification possible. | Limited modification possible. |
| Availability | NoneThe service stays up. | The service stays up. |
Common questions
Is CVE-2023-36846 being exploited?
Yes. CVE-2023-36846 appears in CISA's Known Exploited Vulnerabilities catalog, which means exploitation in the wild has been confirmed and reported. Treat it as active rather than theoretical, and patch it ahead of higher-scoring vulnerabilities that carry no exploitation evidence.
How severe is CVE-2023-36846?
CVE-2023-36846 is rated Medium with a CVSS score of 5.3. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2023-36846?
Yes. A fix has been recorded for CVE-2023-36846. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2023-36846 affect?
CVE-2023-36846 affects juniper:junos. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
References
2 references in the CVE record, grouped by the tags the record gives them.
Advisories (1)
- supportportal.juniper.net /JSA72300
Other links (1)
- cisa.gov /known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-36846
Where the data on this page comes from
- CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
- NVD: CVSS and CPE data
- CISA KEV catalog: exploitation, date added, due date
- CISA Vulnrichment (ADP): SSVC decision points
- FIRST EPSS: exploit probability and percentile
- PoC-in-GitHub: GitHub repositories that claim a proof of concept
Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.
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