Malicious PDF — malware analysis report

Static analysis result for SHA-256 afb43b77a4ee162f…

MALICIOUS

PDF

93.7 KB Created: 2021-09-13 18:03:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 945094b26637a0e74717c36d997e724d SHA-1: 28c59f715a8e7dc188b5167dbd36f28bbf4985f3 SHA-256: afb43b77a4ee162fbbd2391b102606d9e8e7efb43770c9a80a56478ebbc3c261
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it's a link farm on disposable hosting. The 'SE_PASSWORD_ARCHIVE_LURE' heuristic suggests the document instructs users to open a password-protected archive, a common tactic to bypass gateway security. While no scripts were directly extracted, the PDF structure and numerous unknown URLs point towards a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9918

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://eko-briketes.lv/userfiles/files/fukajozitobaf.pdf In PDF document text
    • http://cy2hand.com/userfiles/vaxiredativivitudanug.pdfIn PDF document text
    • https://beeshark.ro/app/webroot/files/userfiles/files/sareroduxul.pdfIn PDF document text
    • http://keramann.ru/uploads/files/12858937131.pdfIn PDF document text
    • https://shian-jin.com/UserFiles/files/fagamididudel.pdfIn PDF document text
    • http://eprdel.cz/userfiles/file/74277307655.pdfIn PDF document text
    • http://fabtur.ru/upload/files/39816480799.pdfIn PDF document text
    • https://yodishit.com/uploads/userfiles/file/vudadipiwaxoti.pdfIn PDF document text
    • http://anael.fr/fckeditor/userfiles/file/21897519220.pdfIn PDF document text
    • http://andlupa.com/userfiles/file/zuludatag.pdfIn PDF document text
    • https://rh-h1tapi-turbo.com/contents/files/jubex.pdfIn PDF document text
    • http://jca-t.com/fck_image/file/jasinuzamazoxedixure.pdfIn PDF document text
    • http://garderoba.sk/images/_file/niwodisofutoxanavifix.pdfIn PDF document text
    • http://wowbond.com/upload/Fckeditor/file/5310066346.pdfIn PDF document text
    • http://poltinka.ru/userfiles/file/86162327309.pdfIn PDF document text
    • http://herfon-machinery.com/images/ckfinder/files/20210913175634.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/a140c71836799f9c3023b21212715148/fubejerijiwadi.pdfIn PDF document text
    • http://artpolyclinic.com/file/files/32274553661.pdfIn PDF document text
    • http://kowel.com/ckfinder/userfiles/files/1631532121.pdfIn PDF document text
    • http://medtravel.lv/images/hand_uploaded/files/10540951713.pdfIn PDF document text
    • http://korvet-sp.ru/userfiles/file/puwiwuborude.pdfIn PDF document text
    • https://agriplan-rs.com/dados/ckfinder/files/49258538816.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ee8b89cefe---86918025572.pdfIn PDF document text
    • https://sporyolu.com/resimler/files/ropimili.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=android+database+connectivity+with+mysqlPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ed49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED49 11168 bytes
SHA-256: 199190cbde94930a82db4270414411b01654f50da94e40ebe6328104aaa1302e
font_01_sfnt_off00010712.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10712 18764 bytes
SHA-256: 7e5fcaf8baf934b3106b008911138cc1fe193aa655e670dc986296b7c865f6b2
font_02_sfnt_off00013849.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13849 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off0001505a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1505A 17004 bytes
SHA-256: 1433fded29aae041a3fd2a7c201252c8006738d9b88bdf90fb1975ecd3ac5d65