Malicious PDF — malware analysis report

Static analysis result for SHA-256 cba6a21c812f412c…

MALICIOUS

PDF

78.1 KB Created: 2021-09-20 04:57:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 2fb8d53bc4140567e59dd6ec081e9b6a SHA-1: 2effe00e82b7cf5a00eb23fcdfce88901106890b SHA-256: cba6a21c812f412c6dd17d3625dbcc12b50b2b5420902926230fbecf5afd39f9
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. The presence of multiple unknown URLs suggests an attempt to host malicious content or redirect to phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://buildingexpertsdirectory.com/ckfinder/userfiles/files/11899434267.pdf In PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141e3e1a51e6---raboregoparufamibefefi.pdfIn PDF document text
    • http://boekenwinkelindex.nl/images/uploads/30970269480.pdfIn PDF document text
    • https://buzyhub.com/files/puremirajalemawavemokero.pdfIn PDF document text
    • http://geofer.eu/userfiles/files/kakerezizazik.pdfIn PDF document text
    • http://apvn.info/userfiles/file/70447672490.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613723772c311---18899576615.pdfIn PDF document text
    • http://studiodebiaggi.eu/userfiles/files/52206818017.pdfIn PDF document text
    • http://prefinancovaniehypoteky.sk/res/file/34234030459.pdfIn PDF document text
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/jce697skfuctt4vkgs2vma06k4/vasegedega.pdfIn PDF document text
    • http://schokoladenbrunnen.de/idata/zasupubobekolabu.pdfIn PDF document text
    • http://study4student.com/cache/fck_files/file/89227950289.pdfIn PDF document text
    • https://efsanepin.com/calisma2/files/uploads/xakid.pdfIn PDF document text
    • https://combrooncom.com/contents/files/mibisiriwasiwopagiju.pdfIn PDF document text
    • https://adetexfoamgroup.centralcms.cloud/galeria/files/45082679672.pdfIn PDF document text
    • http://nghiencuuykhoa.com/uploads/userfiles/file/32458387789.pdfIn PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/fe449d88ee8459028d481cc8ab4bdf6a/9827157532.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/buaumk1idbvc9au6r1g26imi5i/lotakufa.pdfIn PDF document text
    • http://hanmih.com/userfiles/file/20210908080747.pdfIn PDF document text
    • http://namlinhchisapa.com/userfiles/image/file/rafomisuxuvevit.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/sjmjehnflsqhef1a0vlpac38fe/zenazubawa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=mario+sunshine+64+romPDF 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_off0000cd80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD80 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e597.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE597 10568 bytes
SHA-256: f83190a8e8ee34307fde4546c661581be4bed9672d81ab6881b5f94195f0d663
font_02_sfnt_off0000fd8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD8B 17616 bytes
SHA-256: 1b3520fd15b8f5bf52e4455c84ff1c9f6bcb6262ea6285c9c58b66901404d489