Malicious PDF — malware analysis report

Static analysis result for SHA-256 ace1ea45302ad752…

MALICIOUS

PDF

81.0 KB Created: 2021-09-07 06:53:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 30e73c83cd21f1482325dbe47a9f89fd SHA-1: edaf67fdf1fa6c2dba5a5711f038cb7353bba0ec SHA-256: ace1ea45302ad752dd5a8d25a1dc2ac1768764006a75ad88a5480c959063af3f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://krisoc.ru/uplcv?utm_term=ejercicios+resueltos+de+conversion+de+unidades+de+medida+pdf PDF link annotation
    • https://fishuntpesca.it/file/wusifamefixororu.pdfIn PDF document text
    • https://butchercurnow.com/img/shop//contents/jikezeramevabig.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ad3be7e2fe6---giponipujuvefudaruxopoxem.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16119934dc9566---bupivozino.pdfIn PDF document text
    • https://kumsalgame.com/calisma2/files/uploads/refomelasemamoxer.pdfIn PDF document text
    • https://megatex.ua/images/uploads/file/77216779494.pdfIn PDF document text
    • http://ivankotov.ru/img/lib/file/jufenoj.pdfIn PDF document text
    • http://www.hgbehringer.de/img/files/files/poxezimuwusu.pdfIn PDF document text
    • http://viral-list-monster.com/ckfinder/userfiles/publics/files/tudajavojaferike.pdfIn PDF document text
    • https://carsen.sk/editor_uploads/system/files/85008333424.pdfIn PDF document text
    • http://zrdb-drogbud.pl/Upload/file/35897085298.pdfIn PDF document text
    • http://onsijsselstein.nl/userfiles/files/62635020728.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5dbc767e10---xolemo.pdfIn PDF document text
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/gihil7sv63acgno6e3ib7ulgdi/46300051664.pdfIn PDF document text
    • http://www.texaco.bargiel.com.pl/ckfinder/userfiles/files/zilubidilibasowefaku.pdfIn PDF document text
    • http://starrsgazette.com/admin/images/file/91338899167.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/1976654835.pdfIn PDF document text
    • https://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/1423f81c1ff902351e0d655f3f24a8d2/xaromamirimolusor.pdfIn PDF document text
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/0dp1eglihj3a9hoek32gl41l3r/nisogubusotima.pdfIn PDF document text
    • https://nepalonetours.com/userfiles/files/90722247230.pdfIn PDF document text
    • https://nhachoxebus.com/upload/fck/file/28815665879.pdfIn PDF document text
    • https://dobski.pl/userfiles/file/97665441971.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_off0000d11d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD11D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e92f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE92F 19900 bytes
SHA-256: 899502fff74fa508eef4b1d8e98adb1c89ceefeac4fc76c51471f6aec019c041
font_02_sfnt_off00011c30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C30 11060 bytes
SHA-256: 61732f89857138eb67e383217ac32328b43449713679ee802adb36e0e92cad02