Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b79e07ab1ea83d5…

MALICIOUS

PDF

76.7 KB Created: 2021-06-09 09:23:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-16
MD5: a691f3bcec6b3b8169df48210d4ca258 SHA-1: 50216046dc2caff38ef65f4af04388a90a02f9b2 SHA-256: 5b79e07ab1ea83d50dfec428355a87dcc51162842ae7eafa0b89e4cb2025253a
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many hosted on compromised WordPress installations, suggesting a link farm or phishing lure. The 'ML_NYX_PDF_MALICIOUS' and 'CLAMAV_DETECTION' heuristics strongly indicate malicious intent. The document body, though heavily obfuscated, contains references to 'wkhtmltopdf' and a search term, reinforcing the idea of a deceptive lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://cructi.ru/uplcv?utm_term=all+pokemon+fire+red PDF link annotation
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160a6b160b8b46---lojelizejemizak.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a3fb1e9b55a---50541283835.pdfIn PDF document text
    • https://www.hinogas.com/wp-content/plugins/super-forms/uploads/php/files/sp3gadt4b554m6j8qdn43c27ve/9131816943.pdfIn PDF document text
    • https://soechi.com/userfiles/file/31014203057.pdfIn PDF document text
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a8e05b6ccaf---17311251405.pdfIn PDF document text
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7fc2f3ed1---59423071098.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/16073e71e1de18---sidosok.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160873f2b5314b---43908956074.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091fdef2acc0---17609513580.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071c2dce2949---wabovabimefamufusezo.pdfIn PDF document text
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/9c3v3rs8qogfo01of2uc4rp3pj/94386951348.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/16083b6e3ca79a---xujarodadujuwibufite.pdfIn PDF document text
    • https://www.citysecurity.org.uk/wp-content/plugins/super-forms/uploads/php/files/b7ccu81rqs41p0mdh70blmldmm/sekovonarabixu.pdfIn PDF document text
    • http://artecgroupservices.com/imagenes/file/83091771823.pdfIn PDF document text
    • http://utuin.net/files/fckeditor/file/petikigunopipafadesid.pdfIn PDF document text
    • https://ludifrance.fr/userfiles/file/batexi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f11f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF11F 4852 bytes
SHA-256: ea792dcd6605b8f79b624eea92096564cf357a21cbe23c8402b765461309715a
font_01_sfnt_off0001018b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1018B 10368 bytes
SHA-256: a6de2a367079dbcdddea113d68764d95128ca681e1fa71041dde6b924859d4c3