Malicious PDF — malware analysis report

Static analysis result for SHA-256 e1d924171d2b35a6…

MALICIOUS

PDF

128.5 KB Created: 2021-07-29 22:51:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cc1cbc5016ba5c4b14a1a4730e6a20d1 SHA-1: b92b64dae6334cf4a82a120ef7cd2d48cdfbccfe SHA-256: e1d924171d2b35a62cc8f3771ce8a9b44e16e115cd5eb7d05a5ab7e848849ebf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via a spearphishing attachment. No scripts were extracted, but the URL structure and heuristic firings are sufficient to infer a malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://cructi.ru/uplcv?utm_term=how+to+install+kali+linux+2020
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/ofnd71slp0bv8drroope4tii9l/rulewozolugovabejajon.pdf
    • https://vannordenvastgoed.nl/userfiles/file/86966516115.pdf
    • https://ystechpro.com/nbloom/fckuploads/file/bovigojisobibadigotagon.pdf
    • http://www.findvoters.com/userfiles/file/61663906829.pdf
    • https://teenvolunteerdallas.org/wp-content/plugins/super-forms/uploads/php/files/89137160d059ad6511182356bf3105c1/80317448065.pdf
    • https://kaptenhoki.info/contents//files/wojupowilijojimerexux.pdf
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/160b3de07744bc---56817482106.pdf
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/160803b239f2ec---zajagukuluj.pdf
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/08e30acefab7c944752ddffb0022f9fd/20787841385.pdf
    • http://bfr-bialapodlaska.pl/userfiles/file/legaxemutanixunor.pdf
    • https://speculatio.in/ci/userfiles/files/rukaxobelimegeku.pdf
    • http://perseverance.cyou/updatefiles/file/lobabajes.pdf
    • http://aps-mes.com/files/file/xabedokevofimebeninusagot.pdf
    • https://autosaloncenter.com/uploads/file/99307753511.pdf
    • https://tractorpulling-emmeloord.nl/upload/file/47020830970.pdf
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/59b7811d0d635c7a10c6b8d7ce2623bf/97290218597.pdf
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/16082d4d7158a0---denadedetuxixirumez.pdf
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607c01ea79993---83945284312.pdf
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160beed73a12d3---papolago.pdf
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a7f51510f5---91105341479.pdf
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/8d760d56380340cb79923d19ace1351a/putem.pdf
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160787e498ed61---fososapezope.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000160fd.bin
cec1b04e40505a67981cd5e7a75621ec8ff28542b8695862aee2f163ed580f95
pdf-font-stream PDF embedded font (sfnt) at offset 0x160FD 25188 bytes
font_01_sfnt_off00019f9d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x19F9D 16792 bytes
font_02_sfnt_off0001b7ab.bin
984b82a2611754272ac720c7831cc4cfe207a992b01aa5fca81752bf452f3af6
pdf-font-stream PDF embedded font (sfnt) at offset 0x1B7AB 11684 bytes
font_03_sfnt_off0001db99.bin
32bd0af5af7b1ba141ecf2ca3f61b95e43bfdf18c56a5b4b680a9692b08adcc8
pdf-font-stream PDF embedded font (sfnt) at offset 0x1DB99 10484 bytes