Malicious PDF — malware analysis report

Static analysis result for SHA-256 b931f24aa8f79cc1…

MALICIOUS

PDF

81.3 KB Created: 2021-05-27 04:03:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 7550dc8870722737aa918f47d266443d SHA-1: e4f7c7a8a7b83fa1246c5f79d1527fc59ab4c062 SHA-256: b931f24aa8f79cc174b0a396063ce2fd7d27673ee542b3a7a67a830b9a396b15
156 Risk Score

Malware Insights

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

The PDF file contains numerous links to external websites, many of which are hosted on compromised WordPress installations or disposable domains, suggesting a link farm for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a malicious document designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://laborke.ru/uplcv?utm_term=how+to+reply+email+for+unsuccessful+job+application
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/16076986f23593---wexunoboxiwonematilenifi.pdf
    • https://dolmalatrek.com/userfiles/file/bujanagufusadiwolotime.pdf
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084d4e287199---vevikudejoporopu.pdf
    • http://przedszkolenisko.pl/userfiles/file/17280783816.pdf
    • https://ludifrance.fr/userfiles/file/76654966345.pdf
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5da61815d---70868543535.pdf
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/k0vf89bq17vk7m2oijvl52mcu2/medekekamok.pdf
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090cc0818c32---57519473117.pdf
    • http://augustaelectricalwork.com/editorData/file/46935807751.pdf
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/afc08aabf4f33a23a49da8a501bc8f11/buxufikusipalulowomoju.pdf
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/2m9bc0j29f38louqb4ka3dddd3/78414140959.pdf
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/5ece0017acdd1c0fe78f2099d671c366/76177865287.pdf
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/160850a92ada9d---vizinodu.pdf
    • http://endustriyelkiralama.com/wp-content/plugins/super-forms/uploads/php/files/mnmdt2nm2mptlcue8tmu5fgjn0/sezenolabepot.pdf
    • https://paklya.su/design/img/upload/file/77788352231.pdf
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ffa6b9d671---vaguzugexikadamelexad.pdf
    • https://htddienstverlening.nl/userfiles/file/buwazilobowizema.pdf
    • http://www.misshandicap.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1608a8bd6627a9---xewixumapedepanat.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000db42.bin
486e76e4d91e22d538938342a6e1b76830d2c1296eda8701e8ffba6734106d82
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB42 5532 bytes
font_01_sfnt_off0000ee0a.bin
995d5686362328dbad1825d1a1aa49f275e69321848b6ad1d6cbf57a543aa46b
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE0A 2520 bytes
font_02_sfnt_off0000f932.bin
50c9f8511fb07f2c8e733b7784837a2574547011a1ef28caa06b60f06c857915
pdf-font-stream PDF embedded font (sfnt) at offset 0xF932 10468 bytes
font_03_sfnt_off00011d21.bin
2b0a2192378e6ab26ea1a2853cca26bf62e24bd1730e576d5fee4444468c8005
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D21 16880 bytes