Malicious PDF — malware analysis report

Static analysis result for SHA-256 3ec9ad06bf89a8c9…

MALICIOUS

PDF

68.3 KB Created: 2021-10-08 10:49:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 37099fc865bd29aa831f0865feca700b SHA-1: 42f5b815078a6b99a90039ec274be84fe4dcbeb9 SHA-256: 3ec9ad06bf89a8c9ea7214af0144dfa46869a6d98a60359dd892b624ffc09edc
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF employs a common image-only lure, typical of phishing campaigns, to entice users to click on embedded links. The heuristic 'PDF_IMAGE_LURE' indicates a screenshot-like appearance designed to hide clickable elements. The presence of numerous external URIs, many hosted on disposable domains, further supports a malicious intent, likely for credential harvesting or malware delivery. ClamAV detection and ML classification confirm the malicious nature of the file.

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://inwebjor.ru/uplcv?utm_term=in+objective+c PDF link annotation
    • http://netinflux.net/userfiles/file/togeguvi.pdfIn PDF document text
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613390c8048ec---92199785884.pdfIn PDF document text
    • http://jobsmarttampabay.com/files/public/keguxixavifulosex.pdfIn PDF document text
    • https://classoft.ro/userfiles/file/noniguf.pdfIn PDF document text
    • http://leylasuren.com/images/userfiles/imagefile/gikulajatojelogovulixuve.pdfIn PDF document text
    • http://tasfor.com/files/galeria/files/43919022080.pdfIn PDF document text
    • http://briquettemachinery.com/d/files/85762790513.pdfIn PDF document text
    • http://www.fashiongale.ro/userfiles/files/27945340414.pdfIn PDF document text
    • http://www.abcklima.hu/data/editorfile/pomataniboduz.pdfIn PDF document text
    • http://offerparts.com/upload/files/44063170772.pdfIn PDF document text
    • http://architetturaurbanistica.it/userfiles/files/21221245815.pdfIn PDF document text
    • http://ddservice-bmw.pl/userfiles/file/75381620053.pdfIn PDF document text
    • https://plasterglasgow.com/fwd_docs/file/bavivexi.pdfIn PDF document text
    • http://maytinhnangdong.com/files/uploads/editor/files/74983167050.pdfIn PDF document text
    • https://truongthanhco.vn/webroot/img/files/44649582745.pdfIn PDF document text
    • http://turatabor.hu/media/47354502530.pdfIn PDF document text
    • https://digicpictures.com/downloads/95481845087.pdfIn PDF document text
    • http://cancercareresearch.com/userfiles/file/lanimugidubulozabumut.pdfIn PDF document text
    • http://avandcie-automation.com/ckfinder/userfiles/files/nedute.pdfIn PDF document text
    • http://thecargonepal.com/userfiles/file/63288331115.pdfIn PDF document text
    • https://himalayanthailand.com/image/upload/File/sirulosubize.pdfIn PDF document text
    • http://www.gobarging.com/uploads/textareas/file/76304598947.pdfIn PDF document text
    • http://novo-foto.ru/ckfinder/userfiles/files/zozuguzavapixuferoxonedad.pdfIn PDF document text
    • http://agmapure.com/upload/files/29363166992.pdfIn PDF document text
    • http://esenkardeslerinsaat.com/resimlerfiles/vaniwodep.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_off0000b277.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB277 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ca89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA89 14012 bytes
SHA-256: 37ec96bd1704b4fe14acbf0d1e5299b55cb11fde45d67daca66035abe3c62d08
font_02_sfnt_off0000ed0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED0C 10036 bytes
SHA-256: ff3f18112eacfa8274d6cfef6fab9d29db2fd2b51c379c363907243317d2784e