Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5f08c424cc7f00a…

MALICIOUS

PDF

70.9 KB Created: 2021-10-01 15:20:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 168e862d194f78443e24838f0f230cd8 SHA-1: d68bc08338a1fd7cbb9b08f3069b0b64eaa70424 SHA-256: c5f08c424cc7f00a77736b376740b38d9fa7055f27b0b90d6d4f27301517a450
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that function as a link farm, directing users to potentially malicious websites. Heuristics indicate these links are hosted on compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly support the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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=gta+2+for+android+free+download+apk PDF link annotation
    • http://kapalishakti.com/ckfinder/userfiles/files/riwapojuzekolomuruxeloto.pdfIn PDF document text
    • http://pspectr.ru/userfiles/file/kakapexoruk.pdfIn PDF document text
    • https://cplastik.cz/data/cms/file/kasofutalogefezo.pdfIn PDF document text
    • http://banghetretruc.com/media/ftp/file/53184384248.pdfIn PDF document text
    • https://jooli.ru/ckfinder/userfiles/files/xirutitariva.pdfIn PDF document text
    • http://pooinkki.com/upload/imagesource/file/towuxelokitumemejadinuru.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135093820bfc---17884719542.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/c349aef9c0e20277523e88d9dcde8208/12419258904.pdfIn PDF document text
    • http://jingluo.net/uploadfiles/files/pilizefeva.pdfIn PDF document text
    • http://danies.ru/ckfinder/userfiles/files/87998902425.pdfIn PDF document text
    • http://epicridesnepal.com/files/letipesiraloladegijax.pdfIn PDF document text
    • http://radio-salsa.fr/php/rs/filesupload/file/xojemo.pdfIn PDF document text
    • https://iringmalaysia.com/ckfinder/userfiles/files/90782407182.pdfIn PDF document text
    • http://snp-ent.com/files/fckeditor/file/10522255226155e03664d0d.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/3b443937180c68770667fb37829374f9/panunewakuvam.pdfIn PDF document text
    • http://ingore.cn/upload/files/birijekukuzeletubaxet.pdfIn PDF document text
    • http://spadhotel.com/basefile/spadhotelcom/files/68203149038.pdfIn PDF document text
    • http://yogaschoolofkerala.com/photos/editor/files/nipebukavifeko.pdfIn PDF document text
    • http://deurenhanger.nl/userfiles/file/9498080398.pdfIn PDF document text
    • http://amunt.madteam.net/ckfinder/userfiles/files/rimujesun.pdfIn PDF document text
    • https://mclandpin.com/calisma2/files/uploads/vewidimufowilubagegenage.pdfIn PDF document text
    • https://rieker-consulting.eu/files/file/zabiragu.pdfIn PDF document text
    • http://www.propper-droppers.nl/files/file/vavokevubetimasegalanu.pdfIn PDF document text
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/s7aqa8vku2t2i6c4bbj59mdblb/zakuxuw.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_off0000b382.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB382 10660 bytes
SHA-256: 65acc89e5ec76f83d653a830c779b7e6d7670a2b7a488b007136209da3814b64
font_01_sfnt_off0000cc28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC28 16072 bytes
SHA-256: 1f7b30bda754e3082d491d78323342a5287b4e9604651f8fa370865eb9947769
font_02_sfnt_off0000f57c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF57C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1