Malicious PDF — malware analysis report

Static analysis result for SHA-256 16416197cbd3fa82…

MALICIOUS

PDF

81.8 KB Created: 2021-09-07 06:21:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 8452ad51e828716aa652575ac2700d1b SHA-1: c44d22e23d5f71dd8cbb89bcf14e92821b52a4ea SHA-256: 16416197cbd3fa8222da41ced5a98a09fcc014d704bf9e907376f9b2570694e8
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to external resources, many of which are hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. The presence of multiple links on compromised CMS uploads suggests an attempt to obscure the true destination and leverage trusted-looking domains for malicious hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://chcial.ru/uplcv?utm_term=ugc+net+sociology+syllabus+download+pdf PDF link annotation
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/160aaefe152a3e---xejizewaxuru.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160885531d1d13---69938425700.pdfIn PDF document text
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1607e2f7c4949a---12140896808.pdfIn PDF document text
    • http://assushop.com/userfiles/assushop.com/file/povodaxelojana.pdfIn PDF document text
    • http://immobiliareborghi.com/userfiles/files/butesoruletenolanututulix.pdfIn PDF document text
    • http://kozelskadm.ru/files/uploads/files/80816707347.pdfIn PDF document text
    • http://shopsuathientu.com/uploads/userfiles/file/xupudejo.pdfIn PDF document text
    • https://www.fmworks.com.tr/wp-content/plugins/super-forms/uploads/php/files/ttpq8prlk8bos60isqh3o46kdd/17198880614.pdfIn PDF document text
    • http://anipetkingdom.com/webroot/img/files/diwamozivun.pdfIn PDF document text
    • http://propack-th.com/image/upload/File/71288095246.pdfIn PDF document text
    • http://ferrogep99.hu/static/media/file/41681764308.pdfIn PDF document text
    • http://philboyd.com/93493919938.pdfIn PDF document text
    • https://charlesstreetvideo.com/userfiles/file/47834303370.pdfIn PDF document text
    • https://evermoral.hk/upload/file/1628424487.pdfIn PDF document text
    • https://indacphuc.com/wp-content/plugins/super-forms/uploads/php/files/ugaig55mgls04q5916gvdu5shu/logivezififedovububago.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161150b9916d09---16725546943.pdfIn PDF document text
    • http://www.contal-farmer.com/uploads/files/wobef.pdfIn PDF document text
    • https://digireg.li/upload/wirivewiseg.pdfIn PDF document text
    • https://open-call.fr/uploaded/files/48197344513.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a185700e01a---nogebolipatudipowuwa.pdfIn PDF document text
    • https://www.intermediastudios.com.mx/wp-content/plugins/super-forms/uploads/php/files/adcb79960f04ecdba8b91517d69dcb73/80674479789.pdfIn PDF document text
    • https://ambulatorioveterinariosismondi.eu/file/10018854194.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b486cc26b8c---votavururapawawitewifibe.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_off0000d950.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD950 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f167.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF167 11144 bytes
SHA-256: aeb7a13caafe9a99c31ed19f01a1b2e6a48821faeeba3d13bc55539584c090b0
font_02_sfnt_off00010b38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B38 18044 bytes
SHA-256: 5411bf243502ad93e74c5cd2f1c88fd3a9462f8b2e803c4f23fafe7c78298ac7