Malicious PDF — malware analysis report

Static analysis result for SHA-256 f1a7172d837e9b05…

MALICIOUS

PDF

84.4 KB Created: 2021-07-03 03:19:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c9cc5eabb93bd7f0e5743ae47fbfdfad SHA-1: 25e05d669e1269ec2c557fbb384b290448bc6dab SHA-256: f1a7172d837e9b050d3dc8bb0347c8254148167da6e41c33a0f5854f027318d7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs that point to compromised WordPress sites. These sites, in turn, host other PDF files, suggesting a multi-stage attack designed to lure users into downloading further malicious content, likely for phishing or malware distribution. The presence of external URIs and link farm heuristics strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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 http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160747927245c4---49735299427.pdf
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607273ecf1976---38695699340.pdf
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/a2a46826189a9e17f52ac7b626ffa465/fibuxasomenupawo.pdf
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a7624d89b85---83868921889.pdf
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/160779d65cfcb5---84467021761.pdf
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608181eb4d1c0---bajegubot.pdf
    • http://win-sonic.com/kida2018/ck_imgs/files/79504738702.pdf
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/domfp29ddkt3u0qv45qfu6rdvn/51875270701.pdf
    • https://ensasoft.com.tr/wp-content/plugins/super-forms/uploads/php/files/r6kr1hiqe41644bpppfvsdfmql/vixuzuxeses.pdf
    • https://www.nrlandscapes.co.uk/wp-content/plugins/super-forms/uploads/php/files/b80d6e66ba068559998c7664c4c0bf85/72818158748.pdf
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a364da25c9d---matadevilasuto.pdf
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16090f073521cd---48681571844.pdf
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/4c565bb50a951988018f515fc5847f13/38150769314.pdf
    • http://a-daily.jp/app/webroot/contents_img/files/vuzetikilukezoxubon.pdf
    • http://namngonviet.vn/user-/files/63784328730.pdf
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607f2d1ec7bcc---56939631362.pdf
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/372a8569d3da9f52999b8d23b8cc664e/23527217745.pdf
    • https://www.prowallpanama.com/wp-content/plugins/super-forms/uploads/php/files/30363f457fb9c8e1f9afc602a0dd570d/tunateruxililuxaxozuxi.pdf
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16072bef04eab6---81516103166.pdf
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/8g4jk8hln3elvatp7jk9kr6kf2/korofifanedajan.pdf
    • http://brenna-ski.pl/userfiles/file/kajawexofodaw.pdf
    • http://be-now.pl/userfiles/file/34879408533.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=how+old+will+the+earth+be+when+it+dies
    • 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_off0000e82b.bin
40cfc05c7703ce9fadbc94fc669a9e242e9a6882cb9c4e9451d211b9fbd06c03
pdf-font-stream PDF embedded font (sfnt) at offset 0xE82B 10564 bytes
font_01_sfnt_off00010029.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10029 16792 bytes
font_02_sfnt_off0001183b.bin
9cc733cbbbe5ca1ae9df12d9aff1297545e16a3d2644eedf7d2d63d2c179508b
pdf-font-stream PDF embedded font (sfnt) at offset 0x1183B 16900 bytes