Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9da7ac98785e680…

MALICIOUS

PDF

82.5 KB Created: 2021-06-17 18:05:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 8978449a8a4875f1ff049c08d59e03e0 SHA-1: 850af7655dbe9985f869175a3da63a6b0ca0a869 SHA-256: b9da7ac98785e680ad2337a85012f5c40938fa9543bf6b5ce1b7884e25ee8651
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised WordPress upload storage and disposable hosting, suggesting an attempt to distribute further malicious content or phish users. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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 http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bdecacdea1---41407231401.pdf In PDF document text
    • https://acgroupenterprise.com/userfiles/file/regarebe.pdfIn PDF document text
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/7d763c242585ebbf926ee5fdb9fe6a8c/22832269937.pdfIn PDF document text
    • https://plswa.com/wp-content/plugins/super-forms/uploads/php/files/588f2b592482cd5bf389a7ea02dfe374/vupuzokoxurobawezit.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/grmllbf71t897m670iqf0fu4br/rifizovikitepinodezixinop.pdfIn PDF document text
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606e29301f5b7---katomugupo.pdfIn PDF document text
    • https://getlovebooks.com/wp-content/plugins/super-forms/uploads/php/files/eb6d7405937b8cebfed30be2af1911c1/vurisanukogakigo.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/84526511ad3e738b21449a6ee2f8e82a/17967717062.pdfIn PDF document text
    • http://wahibluedevils76.com/clients/5/55/55d7338a7abcce318bc847d7f34994f5/File/xalija.pdfIn PDF document text
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/0e2065580074510f45ded1953a45e751/geriwifezakipagovawaj.pdfIn PDF document text
    • https://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b480daa25ae---mumepezorux.pdfIn PDF document text
    • https://xn--80aaaglcftt5alesfkk7f.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/38aedcec7e5f2013dbddbec328164e72/potozubegabexisasusu.pdfIn PDF document text
    • http://ajivikafinance.com/userfiles/file/jumafitabodilikodobidijup.pdfIn PDF document text
    • http://busanpc1.com/upload/fckeditor/file/10801151208.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/86678632188.pdfIn PDF document text
    • http://bkbflooringusa.com/userfile/abbey/file/26081702752.pdfIn PDF document text
    • http://dyglas.com/userData/board/file/matowiza.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=the+catapult+2+unlimited+coinsPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000105c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105C9 5296 bytes
SHA-256: 1687c97dd4b50e82e837017280186ebccdefc8dc8bcc19884bec8271bd544257
font_01_sfnt_off000117ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117AB 11592 bytes
SHA-256: 332b91164bbc501d68358cc194596b42f3409ac1d1b879c8a896039b03ec8af1