Malicious PDF — malware analysis report

Static analysis result for SHA-256 676d79c2eb25fa49…

MALICIOUS

PDF

82.4 KB Created: 2021-09-08 07:14:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 66ae9873425f438b56e0461206432564 SHA-1: 87df5c8b6ceab86e4df2da1ee4bc682fb0a9a5c3 SHA-256: 676d79c2eb25fa49ad5322d766d30db28e0eab5834fc7163482e9cd565adca41
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised or disposable hosting sites, which is a common tactic for phishing or malware distribution. The presence of numerous PDF links and the use of compromised CMS upload storage further support this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://signexpowholesale.com/project-new/christianbook/upload_images/file/69558393954.pdf In PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079353369fa6---7668995885.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/11b7fa10e69f7bf3c174693eeeec4654/bulewupaxukixubeposama.pdfIn PDF document text
    • http://cabinet-blin.fr/ressource/site-image/files/nijigonukojamujarapuj.pdfIn PDF document text
    • http://szkolaprzybranowo.pl/ckfinder/userfiles/files/92831624580.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a9513902f51---61266919781.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/jebujebejurowaja.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c8cf8c717d1---79103295640.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/3e46bf4820563f91e0d464b7878fb123/66599820644.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160eca15a7c3de---38980763279.pdfIn PDF document text
    • https://www.duffylighting.com/wp-content/plugins/super-forms/uploads/php/files/ed6791b9ff2481d6a485f1e754157ddb/woxugiv.pdfIn PDF document text
    • https://olmitek.by/wp-content/plugins/super-forms/uploads/php/files/3t167oa2ncfe4bf4j1ka6ppff7/susaru.pdfIn PDF document text
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b1a18d1aa9---wijukukotitubemefasi.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/rerenobuvurinafirixepex.pdfIn PDF document text
    • https://infotechsystemsonline.com/ital/www/img/file/kafofevazafu.pdfIn PDF document text
    • https://vgi-vn.vn/app/webroot/img/files/48083893549.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/25cd975334dbe0a376f4625f6f24441b/bixilekokarovamelereriwo.pdfIn PDF document text
    • https://triangle-electronics.com/assets/userfiles/file/75619841881.pdfIn PDF document text
    • http://jadever.vn/Images_upload/files/takazukewipelog.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4882f322ef---divemesozexigule.pdfIn PDF document text
    • https://szekszardportal.hu/userfiles/file/gezuse.pdfIn PDF document text
    • http://nbc.com.vn/ckfinder/userfiles/files/35314779459.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/redivegunapirowibujuk.pdfIn PDF document text
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cfb2dd90e2---85972053097.pdfIn PDF document text
    • http://carlaschroyen.com/content_docs/44240225827.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=spirit+stallion+of+the+cimarron+book+pdfPDF link annotation
    • 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_off0000dcfe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCFE 11192 bytes
SHA-256: 3d08a1ae0aeb552435db29c21241de80bb7298edef6b6cbf899009f1a4cb8b5d
font_01_sfnt_off0000f6b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6B9 17512 bytes
SHA-256: b66d635bc891bbbf80832df32761ff1f3ee21721a68e59c608b810533300682e
font_02_sfnt_off00012401.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12401 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1