Malicious PDF — malware analysis report

Static analysis result for SHA-256 eef95276b34d4649…

MALICIOUS

PDF

82.7 KB Created: 2021-10-19 06:42:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 02f87fa289ac174ecc057145de65f945 SHA-1: d21932f0812e5091472a5d20896ab64a67b3e518 SHA-256: eef95276b34d4649b58b32446c64d89f4f1de77ab9251c5985f34e780c1392b9
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting, characteristic of a link farm. The document body is heavily obfuscated and unreadable, suggesting it's not intended for direct user interaction but rather to host these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://krupongs.com/images/file/47875301440.pdf In PDF document text
    • http://strap.sk/uploads/file/1478733865.pdfIn PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/1615d31b94e5f4---rakewizalapuwibed.pdfIn PDF document text
    • https://luiginoiobbi.com/userfiles/file/zimowitexum.pdfIn PDF document text
    • http://ifaistos.reality.gr/~triantaf/images/file/8532084257.pdfIn PDF document text
    • https://x-leather.com/radsportfiles/file/duweza.pdfIn PDF document text
    • http://xn--80ahcjevtqq.xn--p1ai/ckfinder/userfiles/files/53291691474.pdfIn PDF document text
    • http://eachfun.com/ckfinder/userfiles/site_eachfun_com/files/wuritogoxexinamatafu.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1616c380b98a58---mokag.pdfIn PDF document text
    • https://poganyvolgyi.hu/userfiles/file/15051764750.pdfIn PDF document text
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/d306062233053da4b2fe1a13c85c4e1d/28892215562.pdfIn PDF document text
    • http://leinerpakgelatine.com/survey/userfiles/files/mefidubixegabujowu.pdfIn PDF document text
    • http://veterinariacasettamattei.it/userfiles/files/talixulemimivosopimabuku.pdfIn PDF document text
    • http://ylphs.com/ckfinder/userfiles/files/tujikasokenafo.pdfIn PDF document text
    • http://aedjtj.pretty-match.com/upload/files/ninagopile.pdfIn PDF document text
    • https://www.lsv-wittlage.de/ckfinder/userfiles/files/62999482447.pdfIn PDF document text
    • https://institutdesante.org/userfiles/file/65279859428.pdfIn PDF document text
    • https://curtain.jinware.com/upload/files/lavexoxa.pdfIn PDF document text
    • http://dj-venci.com/uploads/pages/files/68419827106.pdfIn PDF document text
    • http://fine-trading-knotwork.de/uploads/media/15011202411.pdfIn PDF document text
    • https://cian.hr/userfiles/file/walurexajob.pdfIn PDF document text
    • http://vp-dmsh.ru/admin/ckfinder/userfiles/files/kezigiribapazugamelipozul.pdfIn PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614c498812c38---8719137881.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/dofosuzevuvuruzurekajo.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/tgwjJlsMqHc/uplcv?utm_term=are+all+coaxial+cables+the+samePDF 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_off0000df7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF7B 10616 bytes
SHA-256: e4b2327ea1bb9c9b8d1e1765b05889d2cfe1b3294cec3dc39841f1d2f800cbca
font_01_sfnt_off0000f7cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7CC 17620 bytes
SHA-256: cfac4f384711ee9496a9b99545e40f3809c8a6f576c8dd1ea2737fc8c8f6bcca
font_02_sfnt_off00012568.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12568 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1