Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d8606dfb46e61dd…

MALICIOUS

PDF

87.8 KB Created: 2021-06-26 06:18:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b0c4ea264d75cd50ac6567334d6fcc6f SHA-1: e528d4727569339fe61701d1bd5aa19dd62decd7 SHA-256: 8d8606dfb46e61dd6ddc08d68a528ff7acaf7abdef2dfaf7ac752d38cc0aed7c
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, presenting numerous URLs that point to other PDF files hosted on various domains, some of which appear to be compromised CMS upload directories. The primary purpose seems to be directing users to potentially malicious content, possibly for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 http://mayfamilycircle.com/clients/5/53/53cd9f4101e72b768929e5daf979c2da/File/88434221105.pdf
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608148663b75e---49357569154.pdf
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/a0d22b3d4689d24b19529a9426a02f9e/furagavefexido.pdf
    • https://kovosluzba-praha.cz/res/file/simevibidekek.pdf
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/16076a39ed483b---jerupoxaretijojuwebotuwu.pdf
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608293f18ae7b---nabojerokegubad.pdf
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/b75794c62197013d6a64f3105208cd4a/fusajuroxeruwegagebo.pdf
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/6826368d50e9f928e33a805b4aa1fead/wosuximefavometuna.pdf
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/664c3917e7f1b315f73f16bae7beebce/gapokone.pdf
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16091dae08329c---zixulunewur.pdf
    • http://pvvc.cz/files/71684166892.pdf
    • http://tutaylamhet.com/storage/ckfinder/files/jilematupekefirape.pdf
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607e0842d3fbb---63594479204.pdf
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083b89b11ad0---81946930892.pdf
    • https://makeswebsites.com/clients/c/c8/c8c605999f3d8352d7bb792cf3fdb25b/File/wilivogor.pdf
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607a194968c2b---buzekemufufarimabebaze.pdf
    • http://toshiba-center.ru/uploads/files/33833977830.pdf
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160935082adc54---9913904353.pdf
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608679276ab7c---4547929236.pdf
    • https://www.alphaveneers.com/wp-content/plugins/super-forms/uploads/php/files/c7d7cc348f33e4be0c608085f3fbb7d5/vudibeji.pdf
    • http://engineersclasses4competition.com/files/others/54360836061.pdf
    • https://castel.ro/userfiles/file/23620535088.pdf
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/16083e26030ee4---88133656257.pdf
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/726nj68ik88cob80r9sj8tqfv6/fanukijex.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=title+page+with+abstract
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f5ca.bin
7b713a7cdb243c8b05d229bd5c48b4fe3ac867fc69ffdec10788eb59cd945a08
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5CA 16968 bytes
font_01_sfnt_off000121d2.bin
0ce074a89aef8c58424dd928669561d420706963c9833321531b9bfc708a335d
pdf-font-stream PDF embedded font (sfnt) at offset 0x121D2 10620 bytes
font_02_sfnt_off00013a19.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13A19 16792 bytes