How severe is CVE-2026-35536?

CVE-2026-35536 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2026-35536 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-35536?

CVE-2026-35536 affects Tornadoweb Tornado. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-35536?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-35536 have an EU (EUVD) identifier?

Yes. CVE-2026-35536 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-18574.

When was CVE-2026-35536 published?

CVE-2026-35536 was published on 2026-04-03 and last updated on 2026-06-17.

CVE-2026-35536

CVE-2026-35536 is a high-severity vulnerability in Tornadoweb Tornado with a CVSS 3.x base score of 7.2. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-159.

Key facts

Severity: High (CVSS 3.x base score 7.2)
EPSS exploit prediction: 0% (15th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-18574
Weakness: CWE-159
Affected product: Tornadoweb Tornado
Published: 2026-04-03
Last modified: 2026-06-17

Description

In Tornado before 6.5.5, cookie attribute injection could occur because the domain, path, and samesite arguments to .RequestHandler.set_cookie were not checked for crafted characters.

Frequently asked questions

What is CVE-2026-35536?: In Tornado before 6.5.5, cookie attribute injection could occur because the domain, path, and samesite arguments to .RequestHandler.set_cookie were not checked for crafted characters.
How severe is CVE-2026-35536?: CVE-2026-35536 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2026-35536 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-35536?: CVE-2026-35536 affects Tornadoweb Tornado. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-35536?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-35536 have an EU (EUVD) identifier?: Yes. CVE-2026-35536 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-18574.
When was CVE-2026-35536 published?: CVE-2026-35536 was published on 2026-04-03 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:tornadoweb:tornado:*:*:*:*:*:*:*:*

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