Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf58b3fedcb1b9ef…

MALICIOUS

PDF

95.9 KB Created: 2021-08-18 15:02:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 14a4cdb59f1ddf49fcce5bd2c4de6535 SHA-1: e500d4b0ed1035d94240a45cb027e83b23a4d5db SHA-256: cf58b3fedcb1b9ef1c22a85c5c1ff4a0135c4aeeb382652f927d281f184808b0
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting domains, indicating a link farm designed to lure users to malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://hkxhjfc.ltd/uploads/files/20210630042755.pdf
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1cb43903d5---dovowavexoz.pdf
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160869f6fa4756---gemow.pdf
    • http://arenabilardo.com/data/_files/6334247276.pdf
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/2hlf7qjn1ud2k91cj2hv3gijp5/mifexajupujixo.pdf
    • http://www.caslyn.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606eb9b20f47f---ruworudutukudufiposudit.pdf
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4afaf1c2a3---29344053224.pdf
    • http://rialta.ie/userfiles/files/mefazenofakijumubew.pdf
    • http://bobhendrix-law.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/badigoloxedotozibedogagib.pdf
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/5c91e07f91955b70d8447a1ca44cf7b9/vunagu.pdf
    • http://mea-travel.pl/userfiles/file/57570929085.pdf
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/6cb820054d2d40a681cdac6e98b1296c/52942162626.pdf
    • https://advancedcheckcashadvance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609639f69bd2c---dakajoreboduxusof.pdf
    • http://hoitruyengiaocodocvietnam.com/uploads/image/files/fupadiwezawadalefetuzefef.pdf
    • https://bem-sa.com/img/file/7859244140.pdf
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160994fc3ca9aa---6522603288.pdf
    • http://osoboebludo.com/ckfinder/userfiles/files/32478476172.pdf
    • http://phyllisrubensteinlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/38941322173.pdf
    • http://lawngo.net/fckfiles/nurikibopezamu.pdf
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086bc8c0555b---sufopoxadumuxodisa.pdf
    • https://urbanplace.me/wp-content/plugins/super-forms/uploads/php/files/a2d43606539726d3494e691b1563585f/rajivirifates.pdf
    • https://die-elke.de/cms/elke_page_files/file/93228779005.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=which+electron+configuration+represents+a+violation+of+the+aufbau+principle
    • 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_off0000f99c.bin
1cfb00680a8a18ef5d5af493cc5b57cfe410abeba37087ee2ecd799c98b61e68
pdf-font-stream PDF embedded font (sfnt) at offset 0xF99C 16168 bytes
font_01_sfnt_off00010f34.bin
d99fe40dce98f8e13c8511224a103f01141b6a4d0c54fa9fbacf83474aa68512
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F34 18060 bytes
font_02_sfnt_off00013ed5.bin
1956acf7ae69d5fa1ea125f88a53c6af193aba59593b1e0294a4733dd957d7de
pdf-font-stream PDF embedded font (sfnt) at offset 0x13ED5 11060 bytes
font_03_sfnt_off00015865.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x15865 16792 bytes