CVE-2026-103391 json
Session Smart Router: An attacker-controlled TCP option causes an out-of-bounds write when using the TCP proxy feature
published 12d ago modified 3d ago also EUVD-2026-112226
- cvss
- 5.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 10%
- public exploits
- 0
- none known
Summary
An Out-of-bounds Write vulnerability in the SSR TCP proxy/optimization path in Juniper Networks Session Smart Router allows an attacker to corrupt forwarded packet data and potentially cause a data-plane crash via a transit TCP packet with a crafted TCP option length.
Patch / fix
- Juniper Networks Session Smart Router 7.0.5, 7.1.7, 7.2.3
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 3d ago
Exploit prediction
0.21% chance of exploitation in the next 30 days, higher than 10% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
Affected products
- Juniper Networks Session Smart Router
Classification
- Weakness
-
- CWE-787 Out-of-bounds Write
References
-
supportportal.juniper.net
/JSA112183
vendor-advisory
Sources
- CVE List CVE-2026-103391
- NVD CVE-2026-103391
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