Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef358646ec210086…

MALICIOUS

PDF

84.6 KB Created: 2021-09-23 17:48:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e49fd435e236f1eeb6c6e60a2ac723b7 SHA-1: 898c50ba7bb3dd1bb04089a7e957ec3d6a03d2b8 SHA-256: ef358646ec210086535899444ee91f85e1363a4e4db631805654eb66a41fe097
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF contains numerous embedded URLs, 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 for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, so the rationale is based on the URL heuristics and malware detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://institutdesante.org/userfiles/file/divibage.pdf In PDF document text
    • https://ip-kamera-rendszer.hu/ckfinder/userfiles/files/dedepovubugigipenofepe.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161457a514c953---43267880560.pdfIn PDF document text
    • http://grafitym.kz/files/file/38755849581.pdfIn PDF document text
    • http://emiem.pl/public/upload/ckfinder/userfiles/files/24175603476.pdfIn PDF document text
    • http://cascinamana.it/userfiles/file/bemijowamikigafe.pdfIn PDF document text
    • http://yuanhebiotech.com/upload/files/vodefatiwota.pdfIn PDF document text
    • https://serihosting.com/calisma2/files/uploads/39124454838.pdfIn PDF document text
    • http://cncsprings.com/d/files/zotowevikip.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/16145ad334d02f---bolakoxatexonega.pdfIn PDF document text
    • http://alothongtin.com/upload/FCK/file/14285307907.pdfIn PDF document text
    • http://angel-conference.org/upload_fck/file/2021-9-7/20210907055304380820.pdfIn PDF document text
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/38874469328.pdfIn PDF document text
    • http://gianenricofabro.com/userfiles/files/91474966842.pdfIn PDF document text
    • https://jatransfer.com/userfiles/file/90571360365.pdfIn PDF document text
    • http://miryangpension.com/FileData/ckfinder/files/20210911_B3C285BE5121EABE.pdfIn PDF document text
    • http://mcutech.net/upload/2021/09/file/1631480475491580490.pdfIn PDF document text
    • http://aorganboys.handyfriendship.com/upload/files/30305162577.pdfIn PDF document text
    • http://aolisenjiancai.com/data/files/62028235526.pdfIn PDF document text
    • https://undergroundtakeout.com/userfiles/file/bamifutimo.pdfIn PDF document text
    • http://szmchem.com/userfiles/file/vobozuloxiletubuduzipig.pdfIn PDF document text
    • http://studioguidobarbieri.it/userfiles/files/vovodad.pdfIn PDF document text
    • http://vekosgroup.ru/userfiles/file/45535967560.pdfIn PDF document text
    • http://bradzo-ep.com/uploads/files/31538724577.pdfIn PDF document text
    • http://julianina.de/upload/file/454003212.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=wot+blitz+gold+generator+no+human+verificationPDF 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_off0000e3fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3FA 18168 bytes
SHA-256: 35d033a00244e0b689f1a7028f4b836cd3af8cd9c1e7c571b0f28d40f073c792
font_01_sfnt_off000112ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112EF 11112 bytes
SHA-256: 1b466d4993c7126afbb21192d89937eb560cee3fefa2d3f0e1fbc9680d73efd6
font_02_sfnt_off00012c83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C83 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1