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NVD / CVE Program· CNA mitre

CVE-2020-8986: lib/NSSDropbox.php in ZendTo prior to 5.22-2 Beta failed to properly check for equality when validating the session cookie, allowing an atta

Noroxi assessment

Priority: Monitor (action score 39/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 1.5% (FIRST EPSS); higher than 75% 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.
  • According to the record, no fixed version is available yet.

Low priority for now. Update when a fix is released; follow the vendor's advisory.

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

lib/NSSDropbox.php in ZendTo prior to 5.22-2 Beta failed to properly check for equality when validating the session cookie, allowing an attacker to gain administrative access with a large number of requests.

CriticalCVSS 9.8 · v3.1—No exploit No fix recorded
Published
Mar 24, 2020
Updated
Jun 16, 2026
EPSS
1.5% · 75th percentile

Report tools

JSON

Action score

39

Monitor

Low priority for now.

CVSS
39 / 40 · 9.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 1.5%

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • No fixed version yet

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2020-8986

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi 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.

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Affected 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.

VendorProduct
zendzendto

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • zend zendto3.10
  • zend zendto3.11
  • zend zendto3.12
  • zend zendto3.13
  • zend zendto3.20
  • zend zendto3.51
  • zend zendto3.52
  • zend zendto3.53
  • zend zendto3.54
  • zend zendto3.55
  • zend zendto3.56-2
  • zend zendto3.57
  • zend zendto3.58
  • zend zendto3.59
  • zend zendto3.60
  • zend zendto3.61
  • zend zendto3.62
  • zend zendto3.63
  • zend zendto3.64
  • zend zendto3.65

Same product

zend: all records

Other highest-scoring records for the same primary product.

  • CVE-2021-47667An OS command injection vulnerability in lib/NSSDropoff.php in ZendTo 5.24-3 through 6.x before 6.10-7 allows unauthenticated remote attacke
    51Plan
  • CVE-2020-8985ZendTo prior to 5.22-2 Beta allowed reflected XSS and CSRF via the unlock.tpl unlock user functionality.
    35Monitor
  • CVE-2020-8984lib/NSSDropbox.php in ZendTo prior to 5.22-2 Beta allowed IP address spoofing via the X-Forwarded-For header.
    30Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2013-6808Dec 28, 2013 · Cross-site scripting (XSS) vulnerability in lib/NSSDropoff.php in ZendTo before 4.11-13 allows remote attackers to inject arbitrary web scri
    17Monitor
  • ← EarlierCVE-2018-1000841Dec 20, 2018 · Zend.To version Prior to 5.15-1 contains a Cross Site Scripting (XSS) vulnerability in The verify.php page that can result in An attacker co
    24Monitor
  • Later →CVE-2021-27888Mar 1, 2021 · ZendTo before 6.06-4 Beta allows XSS during the display of a drop-off in which a filename has unexpected characters.
    24Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

No fix version is recorded for this entry. Check the references for vendor advisories.

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

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.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

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
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-754 · Improper Check for Unusual or Exceptional Conditions

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.

References

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records