CVE-2026-82531: Smarty before 4.5.8 and 5.x before 5.8.5 PHP Code Injection via extends: Inheritance Cache
Noroxi assessment
Priority: Monitor (action score 36/100)
- Public proof-of-concept code exists (GitHub); there is no record of exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.82% (FIRST EPSS); higher than 57.7% of all records.
- Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
- Fixed version: smarty-php smarty 4.5.8, 5.8.5.
Low priority for now. Upgrade to smarty-php smarty 4.5.8, 5.8.5 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
Smarty before 4.5.8 and 5.x before 5.8.5 contains a code injection vulnerability where the top-level nocache_hash is never restored during extends:/multi-component template inheritance, leaving it null. Attackers can supply assigned data containing a forged SmartyNocache marker that is copied verbatim into the regenerated PHP cache file, executing arbitrary PHP on include for remote code execution.
- Published
- Oct 6, 2026
- Updated
- Oct 6, 2026
- EPSS
- 0.8% · 57th percentile
- CWE
- CWE-94
Report tools
Action score
36
Low priority for now.
- CVSS
- 36 / 40 · 9.2 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.8%
CISA SSVC decision
- Exploitation
- proof of concept
- Automatable
- no
- Technical impact
- total
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · VulnCheck
- 9.2
- NVD has not scored this yet; the score shown is the CNA’s.
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- Proof of concept exists, no weaponized module
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
Is your version affected? Check itNoroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
—
Versions reported by the vendor
Affected version ranges reported by the assigning authority (VulnCheck). Independent of NVD's CPE analysis and usually ahead of it.
smarty-php smarty
- 4.5.8, 5.8.5not affected
- before 4.5.8affected · semver
- 5.0.0 and later · before 5.8.5affected · semver
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | smarty3 | from 0 | — |
| Debian:12 | smarty4 | from 0 | — |
| Debian:14 | smarty4 | before 4.5.8-1 | 4.5.8-1 |
Same product
smarty-php: all recordsOther highest-scoring records for the same primary product.
- CVE-2024-35226PHP Code Injection by malicious attribute in extends-tag in Smarty29Monitor
- CVE-2026-62993Smarty: SSRF via redirect bypass of trusted_uri using {fetch}27Monitor
- CVE-2026-62996Smarty Security stream restriction bypass through stream: resource27Monitor
Published before and after this one in the same product
- ← EarlierCVE-2026-62992Aug 7, 2026 · Smarty: Symlink path traversal out of trusted directories27Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| smarty-php smarty | 4.5.8 | Vendor (CNA) |
| smarty-php smarty | 5.8.5 | Vendor (CNA) |
| debian:smarty4 | 4.5.8-1 · Debian:14 | Package registry (OSV) |
Exploit status
Proof of concept available
A public proof of concept or detection signature exists. Exploit knowledge is out there; don't delay patching.
Evidence
- Proof-of-concept repository on GitHub ×1
Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.
| Source | Kind | Date |
|---|---|---|
| Proof-of-concept repository on GitHub | stars:2 | 2026-10-07 |
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
- Published
- Fix recordedsame day
- First PoCsame day
- TodayNov 13, 2026+38 d
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
- MegaManSecreporter
Not on record for this CVE: variant or chain candidate · public bounty program.
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- Integrity
- Availability
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- X
Weakness class (CWE)
CWE-94 · Improper Control of Generation of Code ('Code Injection')CVSS vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
Change log
- Exploit maturitynone → poc
- Exploit maturity— → none
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (5 more)Show less
- github.com/smarty-php/smarty/commit/c0fdd4824aca4f67e814b50703cfee1dfde41414
- github.com/smarty-php/smarty/releases/tag/v4.5.8
- github.com/smarty-php/smarty/releases/tag/v5.8.5
- github.com/smarty-php/smarty/security/advisories/GHSA-3w63-v7pm-cq9x
- www.vulncheck.com/advisories/smarty-before-4.5.8-and-5-x-before-5.8.5-php-code-injection-via-extends-inheritance-cache
Vendor advisories and official records. Exploit/PoC links are deliberately left out.