Malicious PDF — malware analysis report

Static analysis result for SHA-256 ad43d2c4b15f2d16…

MALICIOUS

PDF

76.2 KB Created: 2021-07-01 12:46:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 992aa6c378cfac77f51934a34b35b301 SHA-1: 35524dfb5151fcd650a71e4c6a42668126b5ee95 SHA-256: ad43d2c4b15f2d16fd4c31d9e669aa21854869166f3d398270ecc072937bbd5b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links to compromised WordPress sites, suggesting a tactic of hosting malicious payloads on seemingly legitimate but compromised infrastructure. The presence of external URIs and link farms indicates an attempt to distribute or redirect to malicious content, likely for downloading further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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=image+to+dwg+converter+free
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160d66d2c2e1d0---texokawimeg.pdf
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/g3v9itc0a56jbcopglqq2hj4hv/25249925983.pdf
    • http://musthighschool.mn/ckfinder/userfiles/files/28998988488.pdf
    • http://nghiencuuykhoa.com/uploads/userfiles/file/7477053522.pdf
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1607a70c74bc61---55605880443.pdf
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd41305a465---25082188517.pdf
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7ce4f6292d---57100228661.pdf
    • https://rybczewice.pl/userfiles/file/witusunexepivu.pdf
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16080241a5411c---82316027442.pdf
    • http://insidethedigitaltrend.biz/userfiles/file/89121861805.pdf
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/602c94e410585ed06085a7c7af70fd5f/4748405503.pdf
    • http://epsilonsigorta.com/files/202697777.pdf
    • http://red-persimmons.com/upfiles/editor/files/gekivofu.pdf
    • https://jotelek.hu/files/file/74011647267.pdf
    • http://ukicda.com/admin/fckeditor_upfiles/file/2021062813555780554.pdf
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/160d0023c1764f---zugawovobututenup.pdf
    • https://alves.bg/ckfinder/userfiles/files/rifafomag.pdf
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16099c5788d153---kunodosapatexar.pdf
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609008f9b6ea9---39342081435.pdf
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b4978d27b1f---kuxufodudapaxobipis.pdf
    • http://pphu-joanna.pl/fckpliki/file/zimijade.pdf
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/1b11e11dbb7bb69e37d61aa125ec2380/titifubafewebe.pdf
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/aaf46fd66adcf038a77210880ab02bdb/6830789437.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_off0000c86b.bin
1071f4753358f6eaa9819e346a8c571b78bf5d1ced2e6906968079ba18a39db4
pdf-font-stream PDF embedded font (sfnt) at offset 0xC86B 16468 bytes
font_01_sfnt_off0000f344.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF344 16792 bytes
font_02_sfnt_off00010b5b.bin
b8ce2a43ba0c755b217407af0eac29561b3960ac9948ba0aed990459453b67c2
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B5B 10616 bytes