Malicious PDF — malware analysis report

Static analysis result for SHA-256 44eb73b13576e184…

MALICIOUS

PDF

82.0 KB Created: 2021-09-17 00:20:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 3c7892864f3687c960f1389988945918 SHA-1: b17ef4debf3c31e4c2acdbc6f3d4f9711d7a2820 SHA-256: 44eb73b13576e184686da65b7901f717e186d2d159fb933a16b9753cfbf942e2
156 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many of which point to compromised websites or disposable hosting, 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 external URI heuristics and link farm indicators supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://xn----7sbeo1acdy3adh.xn--p1ai/userfiles/file/81365330001.pdf In PDF document text
    • http://www.pes.edu.mn/ckfinder/userfiles/files/kitinepipumazasukuf.pdfIn PDF document text
    • https://tigapilar.com/upload/files/lazam.pdfIn PDF document text
    • http://studiodugnani.it/userfiles/files/muridotuxemagevamijuz.pdfIn PDF document text
    • https://lotusmarinevn.com/upload/files/kupadofijemeruniromubo.pdfIn PDF document text
    • http://zetrade.cz/userfiles/file/netafegixubeba.pdfIn PDF document text
    • http://salkim.com/userfiles/file/fevinoxix.pdfIn PDF document text
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/c49od2qqbcv2cjis331qlcdoh1/texapuvenom.pdfIn PDF document text
    • https://zlatartopalovic.rs/files/jowizorotowozupukodopa.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/502b7799ab9deb5bd2d9fbc44a091898/fuzipugefeguxade.pdfIn PDF document text
    • http://mywayrtk.org/userfiles/file/96894083748.pdfIn PDF document text
    • https://communeouchamps.fr/userfiles/file/93850400076.pdfIn PDF document text
    • http://frutapacargentina.com/ckfinder/userfiles/files/95258533352.pdfIn PDF document text
    • http://www.temaricerca.com/entry2013/admin/ckfinder/userfiles/files/bidusan.pdfIn PDF document text
    • https://vwb.mrv-educationservices.com/content_file/files/72015164551.pdfIn PDF document text
    • https://saatyapi.com/upload/ckfinder/files/mikukoke.pdfIn PDF document text
    • http://gsxr.hu/userfiles/file/97868888287.pdfIn PDF document text
    • https://www.solucionaesp.com/ckfinder/userfiles/files/kimetoloxibilolivonekule.pdfIn PDF document text
    • http://dungcubepgiangtrinh.com/webroot/img/files/30057085904.pdfIn PDF document text
    • https://bandai-k.com/userfiles/file/zagafomumejorejuvotox.pdfIn PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/16140e5aa89b36---xapanogubolanasu.pdfIn PDF document text
    • http://theclelandgroup.com/img/upload/file/14702327319.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=gta+5+mobile+skip+human+verification+apkPDF 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_off0000d840.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD840 11316 bytes
SHA-256: 795b5740cc9ad473e2eaa157e41e079ab08d1c355a3df21603735a8eac975391
font_01_sfnt_off0000f28f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF28F 18808 bytes
SHA-256: 94ea92a377d3fa05f88cdc1274e5f17c4febecc61fbba208874199ea0a1fbb05
font_02_sfnt_off00012213.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12213 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1