Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3cd1a34d6e27acb…

MALICIOUS

PDF

82.1 KB Created: 2021-09-14 12:30:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 531d55a72eb8b2985cb8633590721dbb SHA-1: 8826511aeb9ca0be0d74711419a6499fe5ecd149 SHA-256: c3cd1a34d6e27acb32ceefc0735316d84eba6d553a6f6796ad76f330d145efae
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous external URIs and link farm heuristics, suggesting it is designed to redirect users to potentially harmful websites. The presence of multiple compromised CMS upload links further supports this, as these are often used to host malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://laborke.ru/uplcv?utm_term=the+secret+principles+of+genius+free+download PDF link annotation
    • http://ballmillfactory.com/d/files/zaziwokonimi.pdfIn PDF document text
    • https://campfun.myhost888.com/upload/ckeditor/files/zibuzemalo.pdfIn PDF document text
    • https://laps.pl/userfiles/file/20461327274.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161303319dcfb2---jopodidajasup.pdfIn PDF document text
    • https://rwd1.thadv.com/upload/files/14220508631.pdfIn PDF document text
    • http://sapientgenerator.ru/files/userfiles/files/xojafozar.pdfIn PDF document text
    • http://textstricker.de/benutzerdateien/gajap.pdfIn PDF document text
    • http://www.dfdtrading.sk/ckfinder/userfiles/files/3274474681.pdfIn PDF document text
    • https://aiwatopup.com/ckfinder/userfiles/files/susemagelenadagoluluveka.pdfIn PDF document text
    • http://ultrabeauty-ff.ru/userfiles/file/8769917118.pdfIn PDF document text
    • http://hz-kontejnery.cz/ckfinder/userfiles/files/femopuxelas.pdfIn PDF document text
    • http://celcg.pl/uploaded/file/dojanirebofimiparos.pdfIn PDF document text
    • http://rc-mst.com/mst/_upload/files/jutim.pdfIn PDF document text
    • http://group-anons.ru/userfiles/files/ripokewoduj.pdfIn PDF document text
    • https://swagath.co/new/ckfinder/userfiles/files/tasapetis.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139e34ea9a71---sewavomuxavatikevewam.pdfIn PDF document text
    • http://nilesk.com/userfiles/file/guvogutubodudeb.pdfIn PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/ojkpkojsjkgaqsi55kvauph7rm/15554423146.pdfIn PDF document text
    • https://equator-maritime.com/userfiles/file/sotusosofeb.pdfIn PDF document text
    • https://viessmannboilers.ca/fck_upload/file/10564314505.pdfIn PDF document text
    • http://www.seminariomenorvalencia.com/admin/lib/ckfinder/userfiles/files/79213789493.pdfIn PDF document text
    • http://inbeeldt.nl/userfiles/file/seluluzib.pdfIn PDF document text
    • http://videotour24.com/data/fckupload/file/52241173703.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_off0000daeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAEB 17556 bytes
SHA-256: d223cc6532f9d1f8bac2ad2e4f8ee2dab0b3828bb50fcd3f7bc30c9b899f0471
font_01_sfnt_off000108c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000120dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120DD 11048 bytes
SHA-256: 4384e071a233384aa439e3598f9344e4a86506629a697609343a73eaae3bfd34