Malicious PDF — malware analysis report

Static analysis result for SHA-256 c98b66e55390dd64…

MALICIOUS

PDF

84.8 KB Created: 2021-09-05 09:46:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 13b88c2c4b9010c48f20160941777b1a SHA-1: 180b4d12bddebbe8a0380b0a111f6ce940ac269a SHA-256: c98b66e55390dd64537d85a215eed9db91f08db1b564aff26acdd0ead29e92ca
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, suggesting a link farm designed to lure users into downloading further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://crewmak.ru/uplcv?utm_term=10th+economics+book+pdf+download PDF link annotation
    • https://cerquilho.sp.gov.br/public/admin/globalarq/uploads/files/20518287396.pdfIn PDF document text
    • http://change4best.ru/upload/file/mevutivuzuzeno.pdfIn PDF document text
    • http://italianopizzeria-pg.com/uploads/files/rixusafuwesiwifud.pdfIn PDF document text
    • http://brukbet.com/user_images/file/vojanogutugolewotalub.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160854d667e913---34275399803.pdfIn PDF document text
    • https://mls.lighting/wp-content/plugins/super-forms/uploads/php/files/33f141e34bea4585199ca50ab7528f32/pemeradevuxad.pdfIn PDF document text
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a75296141a4---fovumivetedap.pdfIn PDF document text
    • https://www.picmephotoboothhire.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606f71040ff1e---42876313732.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16072ad7febf93---sevoxajarakenajoz.pdfIn PDF document text
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c6cf04b87ef---97031947249.pdfIn PDF document text
    • https://www.erenang.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089e1bb82b97---34317605277.pdfIn PDF document text
    • https://thewaves.net/wp-content/plugins/super-forms/uploads/php/files/0nhiqupf0bprrdvn0l4b0mlhv7/13191712260.pdfIn PDF document text
    • http://idealhca.com/admin/images/file/27170710417.pdfIn PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bef5f3d67da---sekiw.pdfIn PDF document text
    • http://ozkayalarlojistik.com/userfiles/file/mixilesisinu.pdfIn PDF document text
    • https://jollytime.ru/wp-content/plugins/super-forms/uploads/php/files/da5f780a01394e800bcaadc05b03f34e/nifadepirupodekavisogiku.pdfIn PDF document text
    • https://spbmworld.com/anaeter_capital/siteadmin/userfiles/files/bupuleroranovad.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078cfecb5d64---4029906456.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607100f556b9f---mijijeg.pdfIn PDF document text
    • http://mkngsp.ru/upload/files/bukibukurajod.pdfIn PDF document text
    • http://giaexploring.it/userfiles/files/kikobozi.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0132b2f2ac---95710031356.pdfIn PDF document text
    • http://patroha.hu/file/70142890002.pdfIn PDF document text
    • https://clumba-indoor.ru/files/files/bexokesamuxuzopipe.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/umja6gb1vvv0q5cdvltgpmr705/82469808252.pdfIn PDF document text
    • http://ecoaga.com/documentos/file/21200213002.pdfIn PDF document text
    • 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_off0000df19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF19 11180 bytes
SHA-256: d46295cdf9d4a0c4da9771dfdd94411c444db49da4ed825b80d085e1e528148d
font_01_sfnt_off0000f8e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8E6 19900 bytes
SHA-256: b11c277da18a66a8b98e8ce93782b314d190695f108e5aeccd8b579aed5485b5
font_02_sfnt_off00012d70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D70 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1