Malicious PDF — malware analysis report

Static analysis result for SHA-256 f63c10f6b7ee4f37…

MALICIOUS

PDF

68.7 KB Created: 2021-09-13 18:48:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 149b485763f7802359bcd432098e759a SHA-1: 2ccdb752c2b9c427ef3d38455c08bead860cb8b7 SHA-256: f63c10f6b7ee4f37244176f6d27fd6c4bb6bd4bb35c8e6325594307bd1829c4b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics as containing a link farm and pointing to compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded URLs suggest a phishing or malware distribution scheme, likely using a spearphishing attachment as the initial access vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 https://coretry.ru/uplcv?utm_term=how+to+do+time+lapse+video+on+android PDF link annotation
    • http://solarhomepage.ch/fckeditor/editor/images/file/tasoxupenifunudam.pdfIn PDF document text
    • http://nextgenship.net/upload/file/20210902163056150952.pdfIn PDF document text
    • http://pnktools-th.org/ckfinder/userfiles/files/6722999208.pdfIn PDF document text
    • http://stylekd.ru/files/67892488702.pdfIn PDF document text
    • http://autodilygood.cz/files/file/winalikajazixirilodo.pdfIn PDF document text
    • http://skyrybupaslaugos.lt/uploads/files/89775609892.pdfIn PDF document text
    • http://automsystem.com/UploadFile/file/20210913015620554.pdfIn PDF document text
    • https://condicionamentofisico.com/arquivos/file/5145175193.pdfIn PDF document text
    • https://groupburuemas2.com/contents/files/zixosaromoxirasokera.pdfIn PDF document text
    • https://atputasbaze.lv/images/userfiles/files/49689903534.pdfIn PDF document text
    • http://aias.pnu.ac.th/ckfinder/userfiles/files/42656128349.pdfIn PDF document text
    • http://saeronbio.com/userData/board/file/wofobajesakun.pdfIn PDF document text
    • http://topoint.cc/userfiles/fckFile/20210906061907.pdfIn PDF document text
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138171e45ecc---58898725453.pdfIn PDF document text
    • https://trinityautorepairs.com/uploads/files/44205982668.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613df8f9143ec---losat.pdfIn PDF document text
    • http://fabtur.ru/upload/files/defen.pdfIn PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138138ee7906---lazow.pdfIn PDF document text
    • http://yakutiaprime.ru/SITE/files/editor/file/judojegedezevedetutemek.pdfIn PDF document text
    • http://fzcce.com/aimgs/uload/files/45012817471.pdfIn PDF document text
    • http://fisioterapiasuzzara.it/userfiles/files/kopijus.pdfIn PDF document text
    • http://alphasigmaoverseas.com/userfiles/file/benojeju.pdfIn PDF document text
    • http://deborahmayerlawoffices.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gilinuwamizorudekugaz.pdfIn PDF document text
    • https://marosme.ro/hirek/file/13358678607.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_off0000b07f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB07F 10696 bytes
SHA-256: 4dbc6ed5ce4b4bb079840d8b2a2f615c1eef8ef0feba89f96ab5ce67d45a3b09
font_01_sfnt_off0000c904.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC904 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e116.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE116 14520 bytes
SHA-256: 35436c8a5d0e7c45cba873802ee459d9b603e85a5027759b9f1b8b76df5930eb