Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac45b833bf1d682c…

MALICIOUS

PDF

69.5 KB Created: 2021-09-19 02:19:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 739f171ba21022c818949b6c03fd83a3 SHA-1: 579fc8be9da44b097d3f8b2ed740ba4acae75d7b SHA-256: ac45b833bf1d682c7513578c42aa4731e4d278d555acfdb775686173ccdea132
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links, many pointing to compromised WordPress sites, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links. The presence of multiple external URIs and link farm heuristics supports this attack pattern.

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://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/9be2fae29ab1c0d197c69f329521c70f/3972912181.pdf In PDF document text
    • http://tuzy.pl/Upload/file/10164206481.pdfIn PDF document text
    • http://boekenwinkelindex.nl/images/uploads/jejesilobezevolepisepo.pdfIn PDF document text
    • http://way-of-spirit.ru/upload/file/42627922994.pdfIn PDF document text
    • https://giverny-bkk.com/upload/files/4226085653.pdfIn PDF document text
    • http://wskinbody.com/data/boardData/files/80972603946.pdfIn PDF document text
    • https://8cj2aja7-8mxb.com/contents/files/66239968934.pdfIn PDF document text
    • http://www.waetsukai.jp/system/ckfinder/userfiles/files/15865618760.pdfIn PDF document text
    • https://rafaellopezehijo.com/upload/files/84559337337.pdfIn PDF document text
    • http://richardchong.com/userfiles/files/75041826749.pdfIn PDF document text
    • http://sjhtractor.com/d/files/83928173615.pdfIn PDF document text
    • http://xinge168.com/uploads/files/20210901120451_406705.pdfIn PDF document text
    • http://sinostandards.net/upload/files/papewilofoditofurazifoj.pdfIn PDF document text
    • http://cngwalk.com/fckeditor/userfiles/image/vinunanebadikedipabukakem.pdfIn PDF document text
    • http://domuran.pl/files/file/vivelotirepub.pdfIn PDF document text
    • http://abnicum.com/files/file/raviwulorijuvapelo.pdfIn PDF document text
    • http://premiumcsp.com/uploads/files/tibawuwexexewodaniribiwix.pdfIn PDF document text
    • http://td-mg.ru/uploads/files/48744384388.pdfIn PDF document text
    • http://podarox.ru/public/files/89541634704.pdfIn PDF document text
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/fa3aeb9623f8a56e723d2c67b08f9fa2/98953488278.pdfIn PDF document text
    • https://kuzeyilac.com/resimler/files/53367051027.pdfIn PDF document text
    • https://matras-matrasych96.ru/admin/ckfinder/userfiles/files/maxepuziretisatumesed.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/16143b80f0bd4d---zoxomut.pdfIn PDF document text
    • http://lev-steklo.ru/userfiles/file/10893189556.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=q+and+b+wordsPDF 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_off0000b267.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB267 10156 bytes
SHA-256: ae8572f8359f9491189a37c2d4fda508ce2a1e0dfc7fe66a7277b1a4f755a5c3
font_01_sfnt_off0000c953.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC953 15748 bytes
SHA-256: 5cd4d7cfcffa411e8e619721aeb552070490264f77a763e58cd87b1946896527
font_02_sfnt_off0000f0e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0E3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1