Malicious PDF — malware analysis report

Static analysis result for SHA-256 99ba1502a0911380…

MALICIOUS

PDF

79.8 KB Created: 2021-09-12 23:46:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: aea0907e225856baf6d87286e7312e7b SHA-1: 96bae952bced54a8768d43bd2273254c389bd03a SHA-256: 99ba1502a0911380cb3b161e58f06e2697fd016fa7b10c8213da36bcc6cbd25d
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple embedded URLs that are part of a link farm, with several pointing to compromised WordPress upload directories. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were directly extracted, the structure and embedded URLs suggest an attempt to redirect users to malicious content, potentially exploiting the user's desire to download software or game mods.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 7

  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://catamma.ru/uplcv?utm_term=download+mod+the+sims+free+play PDF link annotation
    • http://autoset66.ru/admin/ckfinder/userfiles/files/digojaj.pdfIn PDF document text
    • https://arslanemlak.com/E/file/In PDF document text
    • http://savytrading.com/userfiles/file/9277548872.pdfIn PDF document text
    • https://zmiz.hr/userfiles/file/30723729644.pdfIn PDF document text
    • http://vodnik48.ru/content/file/nuxotiw.pdfIn PDF document text
    • http://coaching-scolaire.net/userfiles/file/gejoxivazatun.pdfIn PDF document text
    • http://cmrivestimenti.com/userfiles/files/90533592958.pdfIn PDF document text
    • https://officialbacknumber.org/editor_up/27322061970.pdfIn PDF document text
    • http://vitali-schulz-eiskunstlaufen.de/userfiles/files/lukelizogufubawulotel.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/1613853f5898ae---88580013092.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/16138d2ae0de7a---52414105774.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161346006080bf---5448708383.pdfIn PDF document text
    • https://tomorrowhubs.com/upload/users/files/pobijuza.pdfIn PDF document text
    • http://nilesk.com/userfiles/file/zixifaxapezulejodosuri.pdfIn PDF document text
    • https://wtmasonry.com/ckfinder/userfiles/files/zonamos.pdfIn PDF document text
    • https://visualmotion.nl/uploads/file/99092374697.pdfIn PDF document text
    • http://lyzjkgm.com/d/files/biguradoverilosipazoj.pdfIn PDF document text
    • http://komodovo.ru/upload_picture/janoborikenokurugij.pdfIn PDF document text
    • https://magnanerie-cazilhac.com/userfiles/file/fekapezot.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_off0000d441.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD441 10964 bytes
SHA-256: 8ff01973a3c0689ccf7c7abb9c631cc12f58b140c2534dd89902c9ba35a099e8
font_01_sfnt_off0000ed80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED80 17276 bytes
SHA-256: 09ac7c3df0c2610cfed9224c859afe744ecb87dcba82056339421231d0db3c23
font_02_sfnt_off00011a01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A01 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1