Malicious PDF — malware analysis report

Static analysis result for SHA-256 f39388e9117429fc…

MALICIOUS

PDF

77.4 KB Created: 2021-09-16 00:37:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: d57ab7512931b13dd81c1a227a4deb5a SHA-1: 95ef7e99b2d7cc75b8d50872b33940315a95875a SHA-256: f39388e9117429fcc14358d9f649e257b4a84b6ee1c0d4ba83924397fb34c3f0
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, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure and heuristic firings indicate a malicious intent to exploit users via redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://sainaudit.mn/File/89250061432.pdf In PDF document text
    • http://darstin.com/userfiles/files/kekowilagigalemonomax.pdfIn PDF document text
    • http://rosg.net/sa_upload/userfiles/file/20210912194816.pdfIn PDF document text
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/904fd3614bce5fb89a20a2d8683325b5/35699385537.pdfIn PDF document text
    • http://mawaevents.com/uploads/file/93106086950.pdfIn PDF document text
    • https://nationalshield-uae.com/userfiles/files/maguwazipadonudoturewu.pdfIn PDF document text
    • http://ipayon.com/root/FCKeditor/file/wedebuvigefugopus.pdfIn PDF document text
    • http://pttaccounting.com/userfiles/files/23671316375.pdfIn PDF document text
    • http://meruzhankhachatryan.com/app/webroot/files/file/96184070.pdfIn PDF document text
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/b660c01dc14fcc8ca350397407010b3c/mutovowovepezi.pdfIn PDF document text
    • http://www.fashiongale.ro/userfiles/files/42814927780.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133b1d2543a5---34156724679.pdfIn PDF document text
    • https://www.domaine-vrignaud.com/ckfinder/userfiles/files/16923716789.pdfIn PDF document text
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/d5e060c2bbdae7ad6e3132983c2c778d/29033405604.pdfIn PDF document text
    • http://daglichtfilters.nl/ckfinder/userfiles/files/27613985356.pdfIn PDF document text
    • http://web5gstore.com/Files/files/4495035107.pdfIn PDF document text
    • http://otohyundaidanang.com/uploads/image/files/givoluruwonam.pdfIn PDF document text
    • https://christembassybarking.org/wp-content/plugins/super-forms/uploads/php/files/bde2e6f74e3fe3f555c6931385e54192/jafezeko.pdfIn PDF document text
    • http://ahchala.com/img/file/tunefitokativaxem.pdfIn PDF document text
    • http://xn----7sbev0bhje.xn--p1ai/images/news/file/6290844613.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613765a9e5701---60147296441.pdfIn PDF document text
    • https://nisahanpin.com/calisma2/files/uploads/18857485091.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/161408c991ebc0---72589408803.pdfIn PDF document text
    • https://phr4u.com/files/9897799765.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=app+ui+designer+mod+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_off0000c5e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5E2 18888 bytes
SHA-256: c470987cd908444b213581df147475bcac3b028aba7a990dc09bc6d221bdd965
font_01_sfnt_off0000f74c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF74C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010f63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F63 10764 bytes
SHA-256: 1864224dc3546ac1ec36ac70d194cec0c5a136ef84b72be9aaacc4323aa08156