Malicious PDF — malware analysis report

Static analysis result for SHA-256 663bd49209ef7655…

MALICIOUS

PDF

74.1 KB Created: 2021-09-03 03:21:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1ffe50e4671b4010edec5595b6925e42 SHA-1: 3aaa731c186899c2a9306725a5c6965b2f83b5bf SHA-256: 663bd49209ef765517bd8da7935327f72292cd1f31b4e18f0b4ec5899eb1728b
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to direct users to potentially malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious intent. No scripts were extracted, but the extensive use of external links suggests a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 5

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://bibliothequeanglaise.org/bibang/docs/pisoloxopojinokosupakudif.pdf
    • http://kencert.vn/uploads/image/files/mujim.pdf
    • https://grandplaza.bg/uploads/assets/file/40394672872.pdf
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/16103127838355---sixemazitoxumeb.pdf
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fe04379963---wakeretexew.pdf
    • http://wang023spa.com/userfiles/202108file/2021080801501870554.pdf
    • http://msinziniering.com/userfiles/file/69592480472.pdf
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160b06784cb509---73832696143.pdf
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/1faa80i26ipp55j6de2177mfo0/6888326476.pdf
    • http://bezpieczna-strefa.pl/wp-content/plugins/super-forms/uploads/php/files/55ba0e94edf2c260a2bc15bc0f446704/92071553742.pdf
    • http://tuzvedo.hu/elemek/file/woziperiguluno.pdf
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609d18847909f---jiruliror.pdf
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d94c76bc988---6805037590.pdf
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/gejch1u16rsgu1eelsuo2sesm7/tekusutugitinikizivifeped.pdf
    • https://amd-export.com/site/upload/file/xotova.pdf
    • https://carea2plus.com/wp-content/plugins/super-forms/uploads/php/files/ad0b0c9fbe9bc54e7a8eee06887c4047/fosugat.pdf
    • http://datavincity.com/uploads/ckfinder/files/nivagamagusiwavowe.pdf
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/4bf9f187eafdca2904eab8cc6f74d1f6/gixodosekidiwutavedi.pdf
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/16106a5a1eec6b---xudinezitalimolikasarez.pdf
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/hjn9b83dskps6d9h943fjtvrgh/wubebirisijefizemuluxuner.pdf
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608b37862d281---5011176687.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=lector+de+texto+pdf+en+espa%C3%B1ol
    • https://sharpspringwww.kinsta.cloud/wp-content/plugins/super-forms/uploads/php/files/58be8ffef087c35216b6794c450e3f85/35886525260.pdf
    • http://pro.ovh.net/~tribuene/images/banque/file/66571255701.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://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_off0000bcd7.bin
8d5392a73b10d3c85111bb7c3986ebd9234712e6e3acd86b56208233bfee4767
pdf-font-stream PDF embedded font (sfnt) at offset 0xBCD7 17400 bytes
font_01_sfnt_off0000e7f8.bin
5d4f420053f58bd504b4fbed8815f343ae9e23162b4dd11dc72ef7fbd37d0e8c
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7F8 10784 bytes
font_02_sfnt_off000100b3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x100B3 16792 bytes