Malicious PDF — malware analysis report

Static analysis result for SHA-256 99cb867a46197b06…

MALICIOUS

PDF

88.0 KB Created: 2021-07-05 17:10:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2bfa1c92bc6e2da89225095f3849e054 SHA-1: a2fccaad76782950702d01aa3cd6367cfc02eeb0 SHA-256: 99cb867a46197b0647ecaa9b486abad285cb971c76277d04a40fca379937ad76
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or other potentially malicious hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware through these links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL structure and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://littlefreddieking.com/clients/65037/File/24801296069.pdf
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b03501c03b0---21504943925.pdf
    • https://sindonis.com/userfiles/file/vexurafimulizu.pdf
    • http://stuarteisbrucklaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/49874432953.pdf
    • http://tsg-vaganovskoe.ru/ckfinder/userfiles/files/sasoke.pdf
    • http://bfr-bialapodlaska.pl/userfiles/file/68888274762.pdf
    • http://kotolantopeni.cz/file/lezujatiteneke.pdf
    • https://ovalpolycoats.com/media/tigizofevetegemotuse.pdf
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/mvtie96cirglgtjdg4chuf9eip/87070593382.pdf
    • https://www.onestopnaturalstore.ca/wp-content/plugins/super-forms/uploads/php/files/ud5vmcc7lvd4j39qtn89clvmum/kepazugonekawaxomi.pdf
    • https://avistravel.ro/userfiles/file/63030116094.pdf
    • http://africanhairbraidingsalon.com/userfiles/file/zozunapetute.pdf
    • http://quaint-house.com/pisewitadafegitizase.pdf
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/pf5al1h8b7v3e7t6k0c97qgumo/70423857397.pdf
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/49331ee90a50d6bf50eb0e4c73d1dd36/lamovokefapape.pdf
    • https://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160827e1eadaf9---xuwamapufu.pdf
    • https://baigiangtoanhoc.com/upload/files/xabul.pdf
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606fe9b1609f9---nerojuzivezasadisuviloju.pdf
    • http://seednseed.com/admin/fckfiles/file/684046682.pdf
    • https://iphonerepairservice.nl/app/webroot/files/userfiles/files/koliwenes.pdf
    • http://susasoft.com/upload/userfiles/files/kijujig.pdf
    • http://nc-israel.ru/upload/files/61584475071.pdf
    • https://vetamblj.si/ckfinder/userfiles/files/porevotez.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=tintern+abbey+as+a+nature+poem
    • 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_off0000f6bf.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF6BF 16792 bytes
font_01_sfnt_off00010ed1.bin
5fd43180500f107be2e1f95f88976ac1f6342e2ba89f02a218b3eb775d4093b5
pdf-font-stream PDF embedded font (sfnt) at offset 0x10ED1 16348 bytes
font_02_sfnt_off00013908.bin
7fa232c884c8b0cfe27462250255a72f6b910398a4c15c49d7c280630f231f3a
pdf-font-stream PDF embedded font (sfnt) at offset 0x13908 10684 bytes