Malicious PDF — malware analysis report

Static analysis result for SHA-256 57cabaa41815036b…

MALICIOUS

PDF

85.2 KB Created: 2021-06-28 19:04:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c8794e72f1cffc6627b59386f6e9987e SHA-1: d3c71adcffc1a4ffbd7cef1f09dd48161a8beb9c SHA-256: 57cabaa41815036bc8acfff53cd766dc09c049680bdf2abab57d8b02d41f7160
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many pointing to compromised WordPress sites, suggesting a link farm designed to distribute malicious content or conduct phishing. ClamAV detection and ML classification strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a phishing or malware delivery attempt, likely initiated via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://pistant.ru/uplcv?utm_term=cold+war+zombies+how+to+get+pack+a+punch
    • https://vdbergelectro.nl/wp-content/plugins/super-forms/uploads/php/files/598fdde9852345b7b23d212dbe23f553/31327433950.pdf
    • https://thietbivesinhanhhuy.com/asset/files/gedefexelelujutisi.pdf
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160cb1d02441ec---romezojut.pdf
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/57426886e744c34a7b718a74e8ad1d79/99735103965.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081f29fa075d---kekumunenugiza.pdf
    • http://vmkmsz.hu/userfiles/file/83149533669.pdf
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16090e5eaedf86---51365289632.pdf
    • http://atek-ent.com/upload/file/31502505067.pdf
    • http://holidayservicemarsala.it/userfiles/files/24002212427.pdf
    • http://austintownfitch1980.com/clients/879833/File/fexomo.pdf
    • https://utilitydiscount.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fa6f8a683d---42984762555.pdf
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/160add2fb300f4---neguzirururerakitopofolo.pdf
    • https://www.hausbootgeiseltalsee.de/wp-content/plugins/super-forms/uploads/php/files/e713fptc8i40anq3kqbrh64vuc/16723818548.pdf
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160833ce46134b---94883618663.pdf
    • https://freedomhypnosisnyc.com/wp-content/plugins/super-forms/uploads/php/files/ab786f908ea5b44b14bf115333b91843/20029850904.pdf
    • https://frontiersneurophotonics.org/wp-content/plugins/formcraft/file-upload/server/content/files/1/160746be570b29---91394820728.pdf
    • http://kppzp.pl/userfiles/file/38391732009.pdf
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16079fe3561f8d---xupegebumawibafota.pdf
    • https://www.psalighting.com/wp-content/plugins/super-forms/uploads/php/files/6068b013b6f0bb08f58823eadb7eae97/31685807003.pdf
    • https://vieclamday.com/userfiles/file/55220212690.pdf
    • http://thaoduocquyhiem.com/userfiles/image/file/89672687154.pdf
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/c730d321a4d7bcf2582ad4c8fc58ce7e/92604317470.pdf
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/b2f62d5a6bc528233b8741ef874e0ceb/tijamokuzomomo.pdf
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1608a536132d35---kefovuwu.pdf
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/0e84cpdgvdagaalts2q8bg5er1/90035109379.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_off0000e86c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE86C 16792 bytes
font_01_sfnt_off0001007e.bin
c50e9caed987e27e3f27919065bb4c6317d1a42e9ff64be49d83590321670da5
pdf-font-stream PDF embedded font (sfnt) at offset 0x1007E 16404 bytes
font_02_sfnt_off00012b07.bin
15e16b523d2fda5761c99ecf6f68027591ebd767ae2b0af3dcf9342cfa6a9be4
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B07 11468 bytes