Malicious PDF — malware analysis report

Static analysis result for SHA-256 79af34c58c3eb398…

MALICIOUS

PDF

71.4 KB Created: 2021-09-25 13:52:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 50f0699bb7f561d780d2f36e243353c4 SHA-1: c35c4e4617c134dad23f68d3dabb174ff608b686 SHA-256: 79af34c58c3eb398d4d9622cf2a3c318bd315a9080237422b61b23a435bcdc83
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The presence of external URIs and link farms points towards a tactic of directing users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

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 http://kuryakyn.ru/userfiles/file/zaluwuj.pdf
    • http://topstec.com/d/files/60047739512.pdf
    • http://tacchigroup.com/public/thread/risorse/file/jiwuli.pdf
    • http://lltsg.com/uploadfile/file///2021092021344163.pdf
    • https://k85shj16h-561lt.com/contents/files/jukafet.pdf
    • http://www.taxivanclass.com/uploads/ckfinder/files/59783938361.pdf
    • https://christianklein.eu/Quansis/ckfinder/userfiles/files/mujazodoro.pdf
    • http://cpghollywood.com/userfiles/files/72376420647.pdf
    • https://ajansnigde.com/resimler/files/sifivemexinesapasin.pdf
    • http://lesbambousbleus.fr/ckeditor/upload/files/55034993581.pdf
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/161449fcd6beb0---86803609612.pdf
    • https://segurodegranizo.ar/noticias/fckeditor/file/88176361402.pdf
    • http://montazerangroup.com/uploader/file/28538260916.pdf
    • https://shieldtech.cz/ckfinder/userfiles/files/62858785851.pdf
    • http://www.aunay-sous-auneau.fr/ckfinder/userfiles/files/4338033093.pdf
    • http://bulmarconsult.com/files/keresabubozotusalero.pdf
    • https://lbjgold.in/ckfinder/userfiles/files/sejel.pdf
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614019456e519---11062057640.pdf
    • http://protok.pro/upload/files/19975199256.pdf
    • http://indianapit.thriftstorewebsites.net/flash/indianapit.thriftstorewebsites.net/file/68801127725.pdf
    • http://hide-bo.com/img/tmp/file/55525327285.pdf
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140e4fae0c84---95635949175.pdf
    • https://weborder.cloud/userfiles/file///xuposi.pdf
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/161496adcc72ed---81319297151.pdf
    • https://tasivn.com/upload/ck/files/povozusagezowirerog.pdf
    • https://qeyeoptical.com/ckeditor/ckfinder/userfiles/files/sexawimujezowovubidu.pdf
    • http://acelybio.com/upload/files/40662864142.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=recuva+free+download+for+android+mobile
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b3c7.bin
b4c90b313cb6fd7d1dbd78e9470ff833bbaf590808c90b96507247b672ed471b
pdf-font-stream PDF embedded font (sfnt) at offset 0xB3C7 10808 bytes
font_01_sfnt_off0000cca9.bin
838827a2ba2f7b124b68536a2678c8c49383166dfdef52c1111698d49c03bb54
pdf-font-stream PDF embedded font (sfnt) at offset 0xCCA9 16836 bytes
font_02_sfnt_off0000f73d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF73D 16792 bytes