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NVD / CVE Program· CNA mozilla

CVE-2025-3029: URL Bar Spoofing via non-BMP Unicode characters

Noroxi assessment

Priority: Monitor (action score 29/100)

  • 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: 0.35% (FIRST EPSS).
  • 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: firefox (AlmaLinux:8) 128.9.0-2.el8_10; thunderbird (AlmaLinux:8) 128.9.0-2.el8_10.alma.1; firefox (AlmaLinux:9) 128.9.0-2.el9_5.

Low priority for now. Upgrade to firefox (AlmaLinux:8) 128.9.0-2.el8_10; thunderbird (AlmaLinux:8) 128.9.0-2.el8_10.alma.1; firefox (AlmaLinux:9) 128.9.0-2.el9_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

A crafted URL containing specific Unicode characters could have hidden the true origin of the page, resulting in a potential spoofing attack. This vulnerability was fixed in Firefox 137, Firefox ESR 128.9, Thunderbird 137, and Thunderbird 128.9.

HighCVSS 7.3 · v3.1—No exploit Fix available
Published
Apr 1, 2025
Updated
Oct 5, 2026
EPSS
0.3% · 29th percentile

Report tools

JSON

Action score

29

Monitor

Low priority for now.

CVSS
29 / 40 · 7.3 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.3%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

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

Follow CVE-2025-3029

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
mozillafirefox
mozillathunderbird

Affected versions

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

  • mozilla firefoxbefore 128.9.0
  • mozilla firefoxbefore 137.0
  • mozilla thunderbirdbefore 128.9.0
  • mozilla thunderbird129.0 and later · before 137.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (mozilla). Independent of NVD's CPE analysis and usually ahead of it.

  • Mozilla Firefox

    • 128.9 and later · up to and including 128.*not affected · rpm
    • 137 and laternot affected · rpm

  • Mozilla Thunderbird

    • 128.9 and later · up to and including 128.*not affected · rpm
    • 137 and laternot affected · rpm

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
AlmaLinux:8firefoxbefore 128.9.0-2.el8_10128.9.0-2.el8_10
AlmaLinux:8thunderbirdbefore 128.9.0-2.el8_10.alma.1128.9.0-2.el8_10.alma.1
AlmaLinux:9firefoxbefore 128.9.0-2.el9_5128.9.0-2.el9_5
AlmaLinux:9firefox-x11before 128.9.0-2.el9_5128.9.0-2.el9_5
AlmaLinux:9thunderbirdbefore 128.9.0-2.el9_5.alma.1128.9.0-2.el9_5.alma.1
Debian:11firefox-esrbefore 128.9.0esr-1~deb11u1128.9.0esr-1~deb11u1
Debian:11thunderbirdbefore 1:128.9.0esr-1~deb11u11:128.9.0esr-1~deb11u1
Debian:12firefox-esrbefore 128.9.0esr-1~deb12u1128.9.0esr-1~deb12u1
Debian:12thunderbirdbefore 1:128.9.0esr-1~deb12u11:128.9.0esr-1~deb12u1
Debian:13firefox-esrbefore 128.9.0esr-1128.9.0esr-1
Debian:13thunderbirdbefore 1:128.9.0esr-11:128.9.0esr-1
openSUSE:Leap 15.6MozillaFirefoxbefore 128.9.0-150200.152.176.1128.9.0-150200.152.176.1
openSUSE:Leap 15.6MozillaThunderbirdbefore 128.9.0-150200.8.206.1128.9.0-150200.8.206.1
openSUSE:Tumbleweedfirefox-esrbefore 128.9.0-1.1128.9.0-1.1
openSUSE:TumbleweedMozillaFirefoxbefore 137.0-1.1137.0-1.1
openSUSE:TumbleweedMozillaThunderbirdbefore 128.9.0-1.1128.9.0-1.1
Red Hat:enterprise_linux:10.0firefoxbefore 0:128.9.0-3.el10_00:128.9.0-3.el10_0
Red Hat:enterprise_linux:10.0firefox-debuginfobefore 0:128.9.0-3.el10_00:128.9.0-3.el10_0
Red Hat:enterprise_linux:10.0firefox-debugsourcebefore 0:128.9.0-3.el10_00:128.9.0-3.el10_0
Red Hat:enterprise_linux:10.0thunderbirdbefore 0:128.9.0-2.el10_00:128.9.0-2.el10_0
Red Hat:enterprise_linux:10.0thunderbird-debuginfobefore 0:128.9.0-2.el10_00:128.9.0-2.el10_0
Red Hat:enterprise_linux:10.0thunderbird-debugsourcebefore 0:128.9.0-2.el10_00:128.9.0-2.el10_0
Red Hat:enterprise_linux:8::appstreamfirefoxbefore 0:128.9.0-2.el8_100:128.9.0-2.el8_10
Red Hat:enterprise_linux:8::appstreamfirefox-debuginfobefore 0:128.9.0-2.el8_100:128.9.0-2.el8_10

+62

Same product

mozilla: all records

Other highest-scoring records for the same primary product.

  • CVE-2010-3765Mozilla Firefox 3.5.x through 3.5.14 and 3.6.x through 3.6.11, Thunderbird 3.1.6 before 3.1.6 and 3.0.x before 3.0.10, and SeaMonkey 2.x befKEV
    94Now
  • CVE-2019-11708Insufficient vetting of parameters passed with the Prompt:Open IPC message between child and parent processes can result in the non-sandboxeKEV
    87Now
  • CVE-2015-4495The PDF reader in Mozilla Firefox before 39.0.3, Firefox ESR 38.x before 38.1.1, and Firefox OS before 2.2 allows remote attackers to bypassKEV
    86Now

Published before and after this one in the same product

  • ← EarlierCVE-2025-2857Mar 27, 2025 · Incorrect handle could lead to sandbox escapes
    41Plan
  • ← EarlierCVE-2025-3028Apr 1, 2025 · Use-after-free triggered by XSLTProcessor
    26Monitor
  • Later →CVE-2025-3030Apr 1, 2025 · Memory safety bugs fixed in Firefox 137, Thunderbird 137, Firefox ESR 128.9, and Thunderbird 128.9
    32Monitor

Remediation

Which version to upgrade to

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

Product / packageFixed versionSource
almalinux:firefox128.9.0-2.el9_5 · AlmaLinux:9Package registry (OSV)
almalinux:firefox-x11128.9.0-2.el9_5 · AlmaLinux:9Package registry (OSV)
almalinux:thunderbird128.9.0-2.el9_5.alma.1 · AlmaLinux:9Package registry (OSV)
debian:firefox-esr128.9.0esr-1~deb12u1 · Debian:12Package registry (OSV)
debian:thunderbird1:128.9.0esr-1~deb12u1 · Debian:12Package registry (OSV)
opensuse:firefox-esr128.9.0-1.1 · openSUSE:TumbleweedPackage registry (OSV)
opensuse:MozillaFirefox128.9.0-150200.152.176.1 · openSUSE:Leap 15.6Package registry (OSV)
opensuse:MozillaThunderbird128.9.0-150200.8.206.1 · openSUSE:Leap 15.6Package registry (OSV)
red hat:firefox0:128.9.0-2.el9_5 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:firefox-debuginfo0:128.9.0-2.el9_5 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:firefox-debugsource0:128.9.0-2.el9_5 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:firefox-x110:128.9.0-2.el9_5 · Red Hat:enterprise_linux:9::appstreamPackage registry (OSV)
red hat:thunderbird0:128.9.0-2.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:thunderbird-debuginfo0:128.9.0-2.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:thunderbird-debugsource0:128.9.0-2.el9_4 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
rocky linux:firefox0:128.9.0-2.el8_10 · Rocky Linux:8Package registry (OSV)
rocky linux:thunderbird0:128.9.0-2.el8_10 · Rocky Linux:8Package registry (OSV)
suse:MozillaFirefox128.9.0-112.252.1 · SUSE:Linux Enterprise Server 12 SP5-LTSSPackage registry (OSV)
suse:MozillaFirefox128.9.0-150200.152.176.1 · SUSE:Linux Enterprise Module for Desktop Applications 15 SP6Package registry (OSV)
suse:MozillaThunderbird128.9.0-150200.8.206.1 · SUSE:Linux Enterprise Module for Package Hub 15 SP6Package registry (OSV)

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.

EPSS, last 120 days

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.

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.

Variant candidates

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

  • CVE-2026-2800329 days apartSpoofing issue in the WebAuthn component in Firefox for Android
    39Monitor
  • CVE-2024-1555406 days apartWhen opening a website using the `firefox://` protocol handler, SameSite cookies were not properly respected.
    33Monitor
  • CVE-2025-14327252 days apartSpoofing issue in the Downloads Panel component
    30Monitor
  • CVE-2026-8960413 days apartSpoofing issue in WebExtensions
    30Monitor
  • CVE-2026-8963413 days apartSpoofing issue in the Web Speech component
    30Monitor
  • CVE-2024-10465154 days apartA clipboard "paste" button could persist across tabs which allowed a spoofing attack.
    26Monitor

Chain candidates

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

  • CVE-2025-281728 days apartPrivilege escalation in Thunderbird Updater
    35Monitor
  • CVE-2025-526456 days apartPotential local code execution in “Copy as cURL” command
    19Monitor
  • CVE-2025-526556 days apartPotential local code execution in “Copy as cURL” command
    19Monitor

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

Weakness class (CWE)

CWE-290 · Authentication Bypass by Spoofing

CVSS vector

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

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.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (5 more)

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

All records