Malicious PDF — malware analysis report

Static analysis result for SHA-256 9723ad5de50ddf4f…

MALICIOUS

PDF

81.3 KB Created: 2021-10-04 17:32:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 7636f371fb4fed1cc8c3f649e11b1b77 SHA-1: d20dd5ded9a3a10262f36bf5a65871db9dde0764 SHA-256: 9723ad5de50ddf4f2e7da5a0fdb99a59c13fe4e72d05ca8f1309405582fddfef
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external links, with several pointing to compromised CMS uploads and disposable hosting, suggesting a link farm used for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://marathonlaval.com/userfiles/files/54771455672.pdf In PDF document text
    • https://ibericadearmerias.com/file/tuxugebipefugopepuko.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614752e7ac556---gexowimomumimiwubosowof.pdfIn PDF document text
    • https://collinite.pl/userfiles/file/83746761315.pdfIn PDF document text
    • http://c-six.it/userfiles/files/18347921496.pdfIn PDF document text
    • https://sangolongphuong.vn/longphuong/news/files/86273803066.pdfIn PDF document text
    • https://libertyrealestate.in/ckfinder/userfiles/files/nuburomumijawalukubetoro.pdfIn PDF document text
    • http://iuf.kr/pds_down/files/73025637965.pdfIn PDF document text
    • https://xn--nmqu14inmf.com/upload/files/84229867390.pdfIn PDF document text
    • http://centreforeffectivecoaching.com/media/file/91311748384.pdfIn PDF document text
    • http://craftland.de/res/wysiwyg/file/59297993169.pdfIn PDF document text
    • https://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/9hgau66omcjskodl4r0rrvtfm3/sebotigurarodefowav.pdfIn PDF document text
    • https://panificioilcavaliere.it/userfiles/files/67229889833.pdfIn PDF document text
    • https://cytokin.ca/upload/editor/file/73204613931.pdfIn PDF document text
    • http://wsystem.sk/userfiles/files/givakulijemubopumobaxifam.pdfIn PDF document text
    • http://thunderstar.cn/userfiles/file/20210907084916911307482.pdfIn PDF document text
    • https://razdolle.by/wp-content/plugins/super-forms/uploads/php/files/oilv3qthqlgta5s30nsrppbuj1/xenosifepirusomum.pdfIn PDF document text
    • https://marblo.ph/app/webroot/img/files/80509620187.pdfIn PDF document text
    • https://f2h63c2.ip4secure.net/upload/files/82662461001.pdfIn PDF document text
    • http://madinagirls.com/easydo%20v2.00/files/uploads/3280417632.pdfIn PDF document text
    • http://hizirferforje.com/admin/fckeditor/editor/images/file/gowufipulovozegunuxu.pdfIn PDF document text
    • https://citrasas.com/userfiles/file/16435542582.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=operation+on+large+numbers+class+5+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_off0000d64a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD64A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ee5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE5C 18552 bytes
SHA-256: d859ffb5219dc965d0be58b4058e6c379b1e44c3b6992679dae8af2e631a7526
font_02_sfnt_off00011d47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D47 11360 bytes
SHA-256: 5c0ddcf91f6b70a94b850a9b08ee493ef2d6d8119767c05649b65399bc40088e