Malicious PDF — malware analysis report

Static analysis result for SHA-256 dfdd111fd8c1befd…

MALICIOUS

PDF

75.0 KB Created: 2021-09-08 21:59:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 2bcd066d96dd92290b6ff28c0011fb9a SHA-1: 4ff47475aae7ad08ac7bca5cceeae639e04c838d SHA-256: dfdd111fd8c1befd522a78295bf9435c8104739fccacd103b0037a7ad1c96789
156 Risk Score

Malware Insights

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

The file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristic analysis revealed that the PDF acts as a link farm, containing numerous URLs pointing to compromised websites. These links are likely used to lure users to phishing pages or download further malicious content.

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://synerhu.ru/uplcv?utm_term=apk+long+form PDF link annotation
    • http://xutricolor.com/uploadfile/files/46135430133.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/3666ac4caacd6ad9a33bcf1e4a42dbf8/97587202981.pdfIn PDF document text
    • http://wonikqnc.com/upload/editor/file/1631008431.pdfIn PDF document text
    • http://twgo8.com/uploads/base/files/202109050832229033.pdfIn PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/85e6ef0be960827f59a4dfff043deb7e/82643564105.pdfIn PDF document text
    • http://mkpstroitel.ru/upload/files/nokaxaw.pdfIn PDF document text
    • http://mosjob.ru/images/file/43570043354.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613149a088c48---9666784953.pdfIn PDF document text
    • http://webinaris.biz/ckfinder/userfiles/publics/files/fikaxebox.pdfIn PDF document text
    • http://chatfieldfarms101.com/userimages/66907836184.pdfIn PDF document text
    • http://moonlightmontessori.com/upload/files/ramus.pdfIn PDF document text
    • https://senesi-sklad.cz/userfiles/file/witokajur.pdfIn PDF document text
    • http://study4student.com/cache/fck_files/file/21088128445.pdfIn PDF document text
    • https://taksis.lv/taksis/userfiles/file/12316630436.pdfIn PDF document text
    • http://dc-07b6a75bc4d0.breakthrough-physical-therapy.com/userfiles/files/86087581977.pdfIn PDF document text
    • https://unitjaya.com/contents/files/45815597538.pdfIn PDF document text
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/161338fdac1473---76458155258.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131d678bdc3d---19898853918.pdfIn PDF document text
    • http://e2ingenieros.com/ckfinder/userfiles/files/rijavezabamav.pdfIn PDF document text
    • http://mp-journal.com/media/file/62662361642.pdfIn PDF document text
    • https://impeka.lt/components/com_mijoshop/opencart/image/data/files/pigexutas.pdfIn PDF document text
    • http://kimwendelldesign.com/ckfinder/userfiles/files/vuxofobujulo.pdfIn PDF document text
    • http://doubler-son-capital.com/photos/files/97773447797.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_off0000c2c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2C4 17564 bytes
SHA-256: d1e738fa72c35782c817cf57af224c0bc8db48dc92485e308c72b1f0cd2abd13
font_01_sfnt_off0000f05f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF05F 10124 bytes
SHA-256: 46f933d1e475e7099ac3ff4eb2ddfdbbfb8b61df96f1f77988110074571a8a36
font_02_sfnt_off000106f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106F0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1