Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5da8e76456a904c…

MALICIOUS

PDF

80.5 KB Created: 2021-09-17 23:29:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: afd8f459429a9034f0d34221c24c9340 SHA-1: 1e1d3811f3c7bb60587eb5f178e58c6bb75db27d SHA-256: b5da8e76456a904c53e8aafad30c0bcc5669ea7d5e865f614337a3fcb72c3633
156 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of multiple external URIs and link farm heuristics points towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://garglob.ru/uplcv?utm_term=instasave+apk+download+old+version PDF link annotation
    • http://mvsexpo.ru/admin/ckfinder/userfiles/files/41910593910.pdfIn PDF document text
    • https://santa.sg/images/users/00000000/files/bemuvojojasekil.pdfIn PDF document text
    • https://km2804.com/ckupload/files/53444939567.pdfIn PDF document text
    • http://xn--9w3b11kh5l.com/ckupload/files/pufewixutuwusa.pdfIn PDF document text
    • http://jenistudio.com/upload/FCK/file/xipujifiluvasiwu.pdfIn PDF document text
    • https://yennenga.org/business_school/uploads/file/713523922.pdfIn PDF document text
    • https://egyptsuntours.com/userfiles/files/kevox.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/5a0f37f0f87088aaa7c73a6ce243f270/xuridekawam.pdfIn PDF document text
    • http://www.contal-farmer.com/uploads/files/nebotaforu.pdfIn PDF document text
    • http://www.photonics-science.com/ckfinder/userfiles/files/87316828390.pdfIn PDF document text
    • http://www.kzhep.in.ua/wp-content/plugins/super-forms/uploads/php/files/40um9gri2ppvqf29jeq6td6u12/nilemivilimusivura.pdfIn PDF document text
    • http://www.evisiontiendaonline.com/ckfinder/userfiles/files/mujowewajudojafezuj.pdfIn PDF document text
    • https://foodsafebox.com/ckfinder/userfiles/files/22853801652.pdfIn PDF document text
    • http://studioaba.net/userfiles/files/jetovapowu.pdfIn PDF document text
    • http://www.tsahimmongol.com/uploads/images/files/xanexadasudorawikajut.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/161384e5db52e1---torigo.pdfIn PDF document text
    • http://larben.cz/media/images/upload/file/nejefanojunijiwimu.pdfIn PDF document text
    • http://jj-metals.com/userfiles/file/2021091612065873499.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/fadbcf4136a3af0e3054920d3d9ade9b/wowesogevemamewujifalodu.pdfIn PDF document text
    • https://www.lsv-wittlage.de/ckfinder/userfiles/files/22609171817.pdfIn PDF document text
    • http://vning.net/filespath/files/20210909120331.pdfIn PDF document text
    • http://fizjoactiv.eu/Upload/file/13721771981.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_off0000d579.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD579 18240 bytes
SHA-256: 1eb97bf903cd0d12814f924b7d6c08472d32c5491ce2fd3d50485e2c0567ffa7
font_01_sfnt_off0001045a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1045A 10580 bytes
SHA-256: 6fcd95757ed5e8fa48e443414805a2a90fbfa7b730592a65abbc7371a097e769
font_02_sfnt_off00011cab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CAB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1