CRITICAL
CVE-2015-1555
CWE-20Published: August 7, 2017· Updated: Jun 17, 2026
9.1
CVSS v3.1
Official Description
Zend/Session/SessionManager in Zend Framework 2.2.x before 2.2.9, 2.3.x before 2.3.4 allows remote attackers to create valid sessions without using session validators.
Technical Analysis
CVE-2015-1555 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), with a CVSS base score of 9.1.
CVSS v3.1 Vector Breakdown
Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityHigh
IntegrityHigh
AvailabilityNone
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Affected Vendors & Products
zend1 product(s)
zend framework
Source: NVD CPE · 13 total CPE entries
Exploit & PoC Resources
NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.
Official Patches & Advisories
All References (2)
→
http://framework.zend.com/security/advisory/ZF2015-01Vendor Advisory
→
http://framework.zend.com/security/advisory/ZF2015-01Vendor Advisory
Quick Facts
CVE IDCVE-2015-1555
CVSS Score9.1 / 10
SeverityCRITICAL
WeaknessCWE-20
CISA KEVNo
Affected1 vendor(s)
PublishedAug 7, 2017
Related CVEs (CWE-20)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2015-1555 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.