Malicious PDF — malware analysis report

Static analysis result for SHA-256 1cd525eab3eea368…

MALICIOUS

PDF

144.6 KB Created: 2021-07-17 18:51:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cb3d25f12a8cd78d108d83f65d9ba453 SHA-1: a5164fa287dcc93b31f2b0d86aaf1577e789934c SHA-256: 1cd525eab3eea368142eab6c14e04b95d7713b2b0d5d6eaecf9bd605a3b83e0b
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous URLs, several of which are hosted on compromised WordPress upload storage. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple external links suggests an attempt to direct the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9369

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://0851gay.org/userfiles/202106file/2021062323462670554.pdf
    • http://shqinze.net/admin/upimg/file///24023758063.pdf
    • http://2016montemayorreunion.com/clients/e/e5/e530e98a7ee505477716bae2fe71cdef/File/44836615778.pdf
    • http://anhuifan.com/upload_fck/file/2021-7-13/20210713154824614842.pdf
    • http://sostrevalli.it/userfiles/files/82501862425.pdf
    • http://savoie-outils-coupants.com/ckfinder/userfiles/files/27892458818.pdf
    • http://cpspcb.com/uploads/files/gawowowireruveb.pdf
    • https://baileyelectrical.services/wp-content/plugins/super-forms/uploads/php/files/nf97gj6l55v6i5o6uohoofo3h5/buzerupilewarixupod.pdf
    • http://anhuifan.com/upload_fck/file/2021-5-1/20210501023241980086.pdf
    • http://generale-bureautique.fr/gdb/files/file/85302543136.pdf
    • http://sibservis.com/ckfinder/userfiles/files/42296242211.pdf
    • https://nomortiga.com/contents//files/51935875946.pdf
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/49474997a50f8f659c45479147587668/4573411567.pdf
    • https://www.synergyheart2heart.team/wp-content/plugins/super-forms/uploads/php/files/4193ib94kjqs6k4epp8ptmqaoh/26844814864.pdf
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a66da0ab606---33734732880.pdf
    • http://makesrealsense.com/ckfinder/userfiles/files/70924870930.pdf
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/cb3bnd7c9icbm2fk229c0vq2tr/67867489190.pdf
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160736a5d07258---zenowezipovubibaxu.pdf
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/1mhhma8bcmm20fabo5849p5mtg/nukakikabawofot.pdf
    • http://mosjob.ru/images/file/pareg.pdf
    • http://al-bandak.com/userfiles/file/91548831290.pdf
    • https://cottonweb.net/userfiles/file/6106553499.pdf
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd5ba723cec---bejamumulasogebavitiwi.pdf
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b561426165a---litetuzivedagamivifexisa.pdf
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/4630b655520ce3ad02fe1c02d95f1053/54170609179.pdf
    • http://vistobrasil.net/uploads/file/2820904284.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=the+heavens+declare+the+glory+of+god
    • 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_off0001abd0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1ABD0 16792 bytes
font_01_sfnt_off0001c3e7.bin
0c9e359f384b9fe5a68acafb19abf4173a7441ffd6ec22260b6a024ddb09eb4e
pdf-font-stream PDF embedded font (sfnt) at offset 0x1C3E7 10808 bytes
font_02_sfnt_off0001dc9a.bin
3c5e9292c15458e2f8032a6682828a5e6af92eead28bb34d77a3b94985ea7d6c
pdf-font-stream PDF embedded font (sfnt) at offset 0x1DC9A 19412 bytes
font_03_sfnt_off0001fdd1.bin
5bd827ad79f3ebdab2286c4a08a5ab41bf83697d7ca8f630980302745441624f
pdf-font-stream PDF embedded font (sfnt) at offset 0x1FDD1 21424 bytes