Malicious PDF — malware analysis report

Static analysis result for SHA-256 13b95e82f7d02856…

MALICIOUS

PDF

76.4 KB Created: 2021-09-17 14:03:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3a5be1aa39a02be7d82ee8c2d03d4e4a SHA-1: 795ca9ec1e5011dc39db9d0daba24383e715e6a8 SHA-256: 13b95e82f7d02856ad21e5a2995a540e81e06bb384dc790ee11aae35a9e97534
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or are hosted on disposable domains, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest a phishing or trojan payload. Although no scripts were explicitly extracted, the nature of the URLs and the PDF structure suggest it's intended to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 https://queure.ru/uplcv?utm_term=faraway+so+close+chords
    • http://phutungquanghieu.com/app/webroot/files/ckfinder/files/lifobanararijebiwozep.pdf
    • http://cesishotel.lv/res/wysiwyg/file/gotiwejikutebufimuv.pdf
    • http://hawaiisushi.iorderfoods.com/uploads/files/fosekewaru.pdf
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/0631b790150883b107b4a5d7b5f247a0/fesadowidokulovagozap.pdf
    • https://rallstarawards.us/nbloom/fckuploads/file/16957916000.pdf
    • https://efckrakow.pl/userfiles/file/29055386706.pdf
    • https://keepingscore.org/userfiles/file/36990162929.pdf
    • https://rentcar888.com/uploads/files/202109090424034312.pdf
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1613102eae7be2---85819157946.pdf
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1612ea5c329324---59343847690.pdf
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133c8babd871---18965110843.pdf
    • http://mvsexpo.ru/admin/ckfinder/userfiles/files/76045284441.pdf
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614062a4da1b1---topugusatigurubuwokaf.pdf
    • https://partetesal.ir/data/file/supuxoguwewetepekalexajel.pdf
    • https://grandiosieventinuziali.it/filesUploads/file/pajonedubotovibafixo.pdf
    • http://agriturismolionsfarm.it/userfiles/files/nugosavesezilurili.pdf
    • https://pacantioquia.org/aym_image/files/bubog.pdf
    • http://piqiso.ru/userfiles/file/62818157874.pdf
    • https://tommytest.dish1314.com/data/html_editor/files/86521724018.pdf
    • https://lazerom.pro/media/file/kujalutomogerofalufere.pdf
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613a09e324ae7---3271222247.pdf
    • https://rugerwafers.com/demo/ruger/beta/userfiles/files/35251443034.pdf
    • http://crocepadrekolbe.it/userfiles/files/vojavomo.pdf
    • 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_off0000c7d9.bin
f7c396e54efd19a5f97edb6382ae9428d3bf75619faf57532ba6a670ba8761b1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC7D9 10352 bytes
font_01_sfnt_off0000df70.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF70 16792 bytes
font_02_sfnt_off0000f782.bin
de1de890341c8d4606d7365640933bd6c5738b07a2cac6177e0f9def3076f22a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF782 17464 bytes