Malicious PDF — malware analysis report

Static analysis result for SHA-256 83345b547894fd17…

MALICIOUS

PDF

75.0 KB Created: 2021-09-13 10:49:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 0c21f3f444f980f1aaaa897fc8600607 SHA-1: 90e45c2c1c967ede91b10e7004dd3c644e79b25d SHA-256: 83345b547894fd175b94c58dcc66ca2b17d2b7e497f72de384ad55f8f24863e8
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The document contains a link farm pointing to multiple compromised CMS upload locations and disposable hosting, suggesting an attempt to distribute malicious content or phish users. The presence of numerous external URIs and the overall structure indicate a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/0ec002d93966338f4df8ec6d80dce74f/turukofu.pdf In PDF document text
    • https://legacydockandmarine.com/wp-content/plugins/super-forms/uploads/php/files/73415e2c7c2e05219c12141896c001a9/zafitoledigokawurug.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161341b2e20454---40659558924.pdfIn PDF document text
    • http://ambvet-trefontane.eu/userfiles/files/30771263407.pdfIn PDF document text
    • https://kattliv.com/kattliv/admin/userfiles/file/35696091625.pdfIn PDF document text
    • https://profm.hu/files/file/13688081621.pdfIn PDF document text
    • http://chapraptti.org/userfiles/file/85677766593.pdfIn PDF document text
    • http://scvumaichiramen.com/uploads/files/61375676220.pdfIn PDF document text
    • http://viral-list-monster.com/ckfinder/userfiles/publics/files/27683226368.pdfIn PDF document text
    • https://www.pharmaright.ca/wp-content/plugins/super-forms/uploads/php/files/jniiutpsrid8ds37rr976ja71f/jikumiz.pdfIn PDF document text
    • https://cowik.pl/upload/92846391406.pdfIn PDF document text
    • http://jujucuisine.com/userfiles/file/kebiretilezebefolekolala.pdfIn PDF document text
    • http://shipsupply.ru/userfiles/files/lalazabupizo.pdfIn PDF document text
    • https://alnahamgroup.com/userfiles/file/sepuwukakekuxuru.pdfIn PDF document text
    • http://80tner.netsociality.com/upload/files/romagotetep.pdfIn PDF document text
    • https://intrigantka.ru/images/userfiles/file/kivezupuwilukarutexur.pdfIn PDF document text
    • http://whipitleather.com/userfiles/file/41073101358.pdfIn PDF document text
    • http://uitvaartverzorgingsindex.nl/images/uploads/58762915501.pdfIn PDF document text
    • http://shanghaiqingchen.com/upload/files/72587175462.pdfIn PDF document text
    • https://www.zochrot.org/ckfinder/userfiles/files/netijopekujivosiwazivew.pdfIn PDF document text
    • http://sunriverps.com/data/editor/file/61873114689.pdfIn PDF document text
    • http://boletos.luzservicos.com/ckfinder/userfiles/files/zenukisezevagasixi.pdfIn PDF document text
    • http://enslev-anlaegsservice.dk/userfiles/file/98513711742.pdfIn PDF document text
    • http://thecuriosityshot.com/77573367596.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=you+have+1+job+memePDF link annotation
    • 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_off0000c402.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC402 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dc14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC14 16904 bytes
SHA-256: 86daf6e88351a495365c81922d2740570a8a4967dd54b413463e70a11d33cda3
font_02_sfnt_off00010780.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10780 10236 bytes
SHA-256: b36900024a763f7083eacb89fde2f53c98e29bea29445e3e790c5c958e508627