Malicious PDF — malware analysis report

Static analysis result for SHA-256 98fa5d7469c31aa3…

MALICIOUS

PDF

82.7 KB Created: 2021-09-21 20:55:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: ca8ba410faf78b4fc5dd860c9c6f11ac SHA-1: e6704012daf7010b983d275524a780e8e45e866e SHA-256: 98fa5d7469c31aa39449b412d8a9dd9aab1728ceb036789fa32f6b6d9b999cf6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links pointing to external PDF files hosted on various domains, suggesting a link farm or SEO poisoning tactic. While no scripts were directly extracted, the nature of the links and the heuristic firings indicate an attempt to redirect users to potentially malicious content, possibly for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://adamant54.ru/userfiles/files/66683402946.pdf In PDF document text
    • http://dejede.com/userfiles/file/38260744453.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/fd16116bd68542d7973071a8be823607/46817995095.pdfIn PDF document text
    • http://delfosventures.com/userfiles/files/rozejogaxavud.pdfIn PDF document text
    • https://derechosenred.org/aym_image/files/79008501027.pdfIn PDF document text
    • http://prtourusa.com/FileData/ckfinder/files/20210915_376DFCEA3103883F.pdfIn PDF document text
    • http://hzxgdz.com/images/upload/File/43309526909.pdfIn PDF document text
    • https://shaplaconsulting.com/app/webroot/ckfinder/userfiles/files/wuzavelixutede.pdfIn PDF document text
    • http://quaisetoiles.fr/img_pages/file/37618292502.pdfIn PDF document text
    • http://ncdesign.it/userfiles/files/ranudadirog.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/vpjipp2uf41qoft0dh33u2hlq2/13643632626.pdfIn PDF document text
    • http://xn--b1akwe.xn--p1ai/userfiles/file/gonozipofopojim.pdfIn PDF document text
    • http://aqbnb.com/uploadfile/file/26265616057.pdfIn PDF document text
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/9bc8c6445d1e7a6eee2e9199a5fcd069/dorafadipowil.pdfIn PDF document text
    • https://newcar-rental.com/uploads/files/202109161743222388.pdfIn PDF document text
    • http://chayka-svg.ru/files/56117900039.pdfIn PDF document text
    • http://jpind.pl/userfiles/file/46926899970.pdfIn PDF document text
    • http://truhlarstvi-strakonice.cz/files/file/mulinubasavala.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/16148a92c8af26---kadobivokafogu.pdfIn PDF document text
    • http://iucecb.com/files/file/48933832627.pdfIn PDF document text
    • http://www.fashiongale.ro/userfiles/files/pibidimowomun.pdfIn PDF document text
    • https://fanaf.com/article_ressources/file/51825472039.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=how+to+disable+pop+up+ads+in+androidPDF 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://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000df43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF43 10700 bytes
SHA-256: 847ef61aaa781e32178aa9ecef17fca84c54027a1fbc9f197a6e7d263f01c4bb
font_01_sfnt_off0000f7af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7AF 17708 bytes
SHA-256: 50a212db2980157ffc76fe7b6381d0c2e435b3c5a0eb8a71b91b015205167bbc
font_02_sfnt_off00012504.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12504 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1