Malicious PDF — malware analysis report

Static analysis result for SHA-256 758b5502f66f76bc…

MALICIOUS

PDF

98.3 KB Created: 2021-06-28 20:01:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4699ba221b0fd8e0c48beb0650b1e2c7 SHA-1: f36af80eee909fc8b6a60acf68579753a14d8e6a SHA-256: 758b5502f66f76bcdb69b5831e3eca1febffef34afdc3ee93646e423844bceab
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, likely intended to lure users into downloading further malicious content or visiting phishing pages. The ClamAV detection and ML classifier strongly indicate malicious intent, classifying it as a phishing trojan. The embedded URLs are a primary indicator of the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9928

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://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6145c17dc8---41594637945.pdf
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fa67fd76de---52908119801.pdf
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fbca53d25a---9015191078.pdf
    • http://www.iece.in/userfiles/file/kizevefosivaz.pdf
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/16086a81ba90b0---zivoxomek.pdf
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/8bc81b37c357323dce9194b06ab88e5d/55539737413.pdf
    • https://apc-algercentre.dz/ckfinder/userfiles/files/33855233305.pdf
    • https://vetranhtuongmamnon.vn/wp-content/plugins/super-forms/uploads/php/files/o5a1isfscbf7fh7j0jg7md9pdv/56743620675.pdf
    • http://architects-desk.com/uploadsfile/27795145753.pdf
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074827a7b200---29562701258.pdf
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a916cb36a25---lawuvufibo.pdf
    • https://www.zulilighting.com/wp-content/plugins/super-forms/uploads/php/files/373c5050d720241c64e5156435cdd68f/93037792540.pdf
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/9a7c867668368752f7effe2717ccc5e2/77296268670.pdf
    • https://alyosserspneed.com/userfiles/files/9018517143.pdf
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/d13ec54477b25e5ca4af49f31418ad59/46584063136.pdf
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/inp53c9d0drlnovmq1jnun04g7/12692265137.pdf
    • http://teplospectr.ru/images/files/10202387504.pdf
    • https://nslogisticservice.com/userfiles/files/1200794966.pdf
    • http://staractivecollection.com/resimler/site/files/81316878526.pdf
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c859f384e23---52840708300.pdf
    • http://huiking.cn/uploads/file/121800113497.pdf
    • http://xn--vb0b83rba554gca.kr/page_data/file/20210529221711.pdf
    • http://dolphinegypt.net/userfiles/file/98360928197.pdf
    • http://fitviewer.biz/files/file/gafetijoketosiwovila.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=how+to+cut+an+image+out+of+a+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_off00011d24.bin
1971a3c031af694941cd2d99b7aade389a112e01d62606ccda34604d54701fac
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D24 17664 bytes
font_01_sfnt_off00014b32.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14B32 16792 bytes
font_02_sfnt_off00016349.bin
11671bcaf9e7c0da36560a4d37864ca2c196eadf6f7ef51ec002303de02318e8
pdf-font-stream PDF embedded font (sfnt) at offset 0x16349 10824 bytes