Malicious PDF — malware analysis report

Static analysis result for SHA-256 73c509d3f77f0706…

MALICIOUS

PDF

70.7 KB Created: 2021-09-27 21:31:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 57e8b53683eeb03dec88fd8c5dc42195 SHA-1: 9bb2ea1d569560cc13e68c75bb9e5780d9cecb23 SHA-256: 73c509d3f77f07062aed7661975dbbfdc162874bac32ef55c9bed3192c70e5f2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to lure users into downloading malicious content or providing sensitive information. No scripts were extracted, but the PDF structure itself is designed to facilitate malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://irlanc.ru/uplcv?utm_term=free+fire+magic+hack+apk+download PDF link annotation
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614095db9f88d---42088440015.pdfIn PDF document text
    • http://inimtrento.it/userfiles/files/17770783885.pdfIn PDF document text
    • http://exdebt.bg/userfiles/file/wumokotarekejesin.pdfIn PDF document text
    • https://sentinels.ro/userfiles/file/busorakivurinexobin.pdfIn PDF document text
    • http://humanlitech.com/files/files/73915109338.pdfIn PDF document text
    • https://hglobaltourb2c.com/FileData/ckfinder/files/20210923_4695E5334F232CE1.pdfIn PDF document text
    • http://kzlo.pl/fotki/fotki/file/49510809869.pdfIn PDF document text
    • http://vtaky.sk/media/file/korata.pdfIn PDF document text
    • http://ghalemdi.com/userfiles/file/37196662638.pdfIn PDF document text
    • https://blueparadise.pl/userfiles/file/77150418503.pdfIn PDF document text
    • https://feniks9.ru/ckfinder/userfiles/files/64405778299.pdfIn PDF document text
    • https://bd-sokolovska.eu/userfiles/file/melomav.pdfIn PDF document text
    • https://safetyhanoi.com/userfiles/file/96203808489.pdfIn PDF document text
    • http://lamardaegu.com/upfile/user/file/fewomenomilikapur.pdfIn PDF document text
    • http://rayer.cn/d/files/1250874721.pdfIn PDF document text
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/786d75f784b7f3ad1580c7f2766e791a/55928252570.pdfIn PDF document text
    • https://www.mftelhas.com.br/adm/Editor/ckfinder/userfiles/files/zalisulotukikawap.pdfIn PDF document text
    • https://arerp.kr/data/file///telamunizedidabu.pdfIn PDF document text
    • https://tsolisp.com/files/file/94010617907.pdfIn PDF document text
    • https://nguyenthelong.net/userfiles/files/79964945387.pdfIn PDF document text
    • http://britishcytology.org.uk/ckfinder/userfiles/files/mutuk.pdfIn PDF document text
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/48aa897b7495dd7d4666c8af5ebd1d71/37667702356.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613c01c2f23e2---50540765458.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_off0000af0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF0F 17440 bytes
SHA-256: c89380d9d944c2ea930f359874fd532c9f54f9f02e4d82a601008af30c9b0edd
font_01_sfnt_off0000dc95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC95 10956 bytes
SHA-256: eb43a533728ba22c663f9bb4ef3b6fa818f144f76d7633465f5dd6d9b992910c
font_02_sfnt_off0000f596.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF596 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1