Malicious PDF — malware analysis report

Static analysis result for SHA-256 c27a77d7ba43cc73…

MALICIOUS

PDF

82.5 KB Created: 2021-09-17 18:04:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0f8fe7846c3198f6c8a6192ee8eaaa98 SHA-1: cf458c7a31699877c58703968e7e94938225bab5 SHA-256: c27a77d7ba43cc73f57fd2aa6cd5c0553bfb5f32a893ce2273ce90ae9aee416d
224 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

This PDF document impersonates a cloud file-sharing service, likely to lure users into opening it. The embedded JavaScript stream and multiple external URIs pointing to compromised WordPress sites suggest it is designed to download and execute a secondary payload. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 9

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • 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.
  • Cloud document impersonation lure medium SE_CLOUD_DOC_LURE
    Document impersonates a cloud file-sharing service such as SharePoint, OneDrive, Google Drive, Dropbox, Box, or Microsoft 365 and asks the user to open, verify, or access a shared document
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://pilot-market.ru/new/files/file/wexupulefamexo.pdf
    • http://mgocsm.in/userfiles/file/77387255584.pdf
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dcca669094---32564236474.pdf
    • https://jmclimatizacionhvac.cl/images/subidas/file/tetonekalijede.pdf
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613426c486802---62429925931.pdf
    • https://rdsdealers.com/ckfinder/userfiles/files/43849709828.pdf
    • http://rhondachem.com/d/files/77308038925.pdf
    • http://garmaclima.com/uploads/ckfinder/files/damewitigagakalejelugev.pdf
    • https://nsstore.mx/ckeditor/ckfinder/archivossubidos/files/sepikavopifiwogamineg.pdf
    • http://bsa.by/ckfinder/userfiles/files/tagatufutuzuf.pdf
    • http://heaig.org/editor/ckfinder/userfiles/files/33436297637.pdf
    • https://konferencii.ru/js/ckfinder/userfiles/files/vimaremugedazidanig.pdf
    • http://qdcmd.com/data/files/85586312270.pdf
    • http://samtekelektrik.com/files/84863608931.pdf
    • http://daiichihousing.net/uploads/news_file/kogudojawukagazopelume.pdf
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140bcf4d83f7---zunozejogomu.pdf
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16140f4accab2f---17576083036.pdf
    • http://smartvoicecom.com/userfiles/lemalataso.pdf
    • https://autopsrus.aerovents.com/ckfinder/userfiles/files/lodedolapelibepisukerosaz.pdf
    • https://dehaventransportation.com/home/de/public_html/ckfinder/userfiles/files/45284645587.pdf
    • https://sikahaiphong.com/images/news/files/ziputo.pdf
    • http://kingsap.com/file_media/file_image/file/97318325742.pdf
    • http://samtekelektrik.com
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=how+to+manage+storage+on+android
    • 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_off0000de57.bin
a3479ed3ce91994bbde5c0c93f5edeea11bb4ddc0b4d8fc1f8574082d0683a2e
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE57 10620 bytes
font_01_sfnt_off0000f66a.bin
79bef6e44166d801f2f237b4d130877433d6acf7099fe04bb647623fb726dcb6
pdf-font-stream PDF embedded font (sfnt) at offset 0xF66A 17896 bytes
font_02_sfnt_off000124cb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x124CB 16792 bytes