Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a85b1398b3a41b8…

MALICIOUS

PDF

93.8 KB Created: 2021-03-31 17:48:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 6a55566d4628dd67db31c2d332841547 SHA-1: ba85bd29b567c2d5af05dfdc452f2a53a6824b21 SHA-256: 7a85b1398b3a41b843ad88c82939e8011fe64ef10d9c98cd9729b39090ae1d39
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains an embedded URI pointing to a URL that appears to be a lure for a phishing site, disguised as a calculator tool. No scripts were extracted, but the PDF structure itself facilitated the redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 4

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://golowaki.ru/wix?keyword=desmos+scientific+calculator
    • https://cdn-cms.f-static.net/uploads/4418777/normal_5fd817cb5f67b.pdf
    • https://cdn-cms.f-static.net/uploads/4386613/normal_60640f78cc3c0.pdf
    • http://letilemugemin.66ghz.com/airdroid_app_store.pdf
    • https://cdn-cms.f-static.net/uploads/4451045/normal_603fc45ecefd4.pdf
    • https://cdn.sqhk.co/rozamulev/aei6wie/25251826805.pdf
    • https://cdn.sqhk.co/bosamame/ifidhbO/64613920371.pdf
    • https://cdn-cms.f-static.net/uploads/4412592/normal_5fd625331f92a.pdf
    • https://static.s123-cdn-static.com/uploads/4367941/normal_5fe4149b4fc0d.pdf
    • https://static.s123-cdn-static.com/uploads/4416789/normal_5ffa4721bc084.pdf
    • https://static.s123-cdn-static.com/uploads/4379486/normal_5fe5a3421b4bc.pdf
    • https://cdn-cms.f-static.net/uploads/4403271/normal_602116f7ae0cd.pdf
    • https://static.s123-cdn-static.com/uploads/4411926/normal_6001bcaecf74d.pdf
    • https://cdn.sqhk.co/letarezetap/yziikgg/lutejufe.pdf
    • https://cdn.sqhk.co/rifarako/IjfUiYB/dumadekuze.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/d19ad79a-a3e3-4a56-abd4-0a4157a452c1/20177694228.pdf
    • https://uploads.strikinglycdn.com/files/a86371ad-8136-49e9-9b28-84e810fc5275/cecelia_ahern_where_rainbows_end_quotes.pdf
    • http://votitagupen.epizy.com/certificate_of_occupancy_qld_form.pdf
    • https://uploads.strikinglycdn.com/files/4d948e55-a734-441c-87f3-14673d8da93d/how_to_make_a_daisy_flower_out_of_paper.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000116bc.bin
6d54603d45deb3202ab4ebc3af4bcb196e5fb066a23ed36571ebcb37a2335e1f
pdf-font-stream PDF embedded font (sfnt) at offset 0x116BC 5024 bytes
font_01_sfnt_off000127c4.bin
76fcbc45684c4a30e9fee78c3b0a07c24a32f70a5d41373775278302d8384b89
pdf-font-stream PDF embedded font (sfnt) at offset 0x127C4 14272 bytes
font_02_sfnt_off00015501.bin
c8cad0fcbf711734ba90d1bf0f33d5774ae0d43a5fc07b95f2d0d23150af1919
pdf-font-stream PDF embedded font (sfnt) at offset 0x15501 16088 bytes