Malicious PDF — malware analysis report

Static analysis result for SHA-256 a831a48f7f643d8c…

MALICIOUS

PDF

77.2 KB Created: 2021-07-03 03:27:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 7ab9f87ae13a839c33d1b5a202eca77b SHA-1: cd1e47119029c847f862de34655cd0750ca5a8ff SHA-256: a831a48f7f643d8c50e89bc9bbefc0f659ebad2815bf6111ee6deb51e064453a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file exhibits characteristics of a link farm, with numerous embedded URLs pointing to compromised WordPress sites and other domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were directly extracted, the PDF structure and embedded URLs suggest an attempt to lure users to external, potentially harmful, content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://philabc.ru/uplcv?utm_term=the+story+of+civilization+by+arjun+dev+pdf PDF link annotation
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a330c554816---suwadusidi.pdfIn PDF document text
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/430f8hl5jp3442ajbverbpeeq6/wofigumufudiso.pdfIn PDF document text
    • http://kaies.cn/upfiles/file/jakuz.pdfIn PDF document text
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/a43ceec3dd34d79ec3f47002c82a24da/16565379433.pdfIn PDF document text
    • https://dmvassociates.com/wp-content/plugins/super-forms/uploads/php/files/85e558a53c22a9016eb6bb950fc6de2c/55317606565.pdfIn PDF document text
    • http://collegium-connect.nl/ckupload/files/95204011434.pdfIn PDF document text
    • https://www.eoluk.com/wp-content/plugins/super-forms/uploads/php/files/7i6n734oqfq6ueaorjufoj6s19/59720130955.pdfIn PDF document text
    • http://xn----7sbakn3aoflleitf3m6a.xn--p1ai/userfiles/file/38776471917.pdfIn PDF document text
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1d30d1b699---77312722824.pdfIn PDF document text
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/5ea72c5b77b3f3492af4f852f9a2adfa/14313936400.pdfIn PDF document text
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/eba925d3d673f10ef34f4d9a45e0fdd4/bakametarejavadisema.pdfIn PDF document text
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/077892022cc5a6dd32b5fed439085fd1/kinebewuvofibajana.pdfIn PDF document text
    • https://www.eziblank.com/wp-content/plugins/super-forms/uploads/php/files/cjl4i7p7rjkm2lkudblaa6akh4/19660869996.pdfIn PDF document text
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/16070086e4ec60---xupup.pdfIn PDF document text
    • http://nicenpos.com/userData/board/file/wikotafolawimebo.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8f6577bfd5---63098669937.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160a5565e5df79---21880261613.pdfIn PDF document text
    • http://apvn.info/userfiles/file/51271497347.pdfIn PDF document text
    • http://ansing.nl/userfiles/file/fudegogobix.pdfIn PDF document text
    • https://www.deuba.info/wp-content/plugins/super-forms/uploads/php/files/rv8ou9o0defa571607qph502lb/xedib.pdfIn PDF document text
    • https://pensiuneavalentina.ro/app/webroot/file/xagaw.pdfIn PDF document text
    • http://rivieahk.com/clients/5/51/51325344bd1517f257d6959d5350918e/File/likesisagipejanubomoki.pdfIn PDF document text
    • http://skup-laptopow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b931f88aaa---37404772451.pdfIn PDF document text
    • http://mp-journal.com/media/file/xonumisin.pdfIn PDF document text
    • https://biogenetixpharma.com/ci/userfiles/files/xogavogoworizawavitipepax.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/1606f0afec804a---88325218912.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_off0000c9a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9A2 16588 bytes
SHA-256: 8bc853b9f4088af165ebffded4a5b91bc3a982e61209c06018c64d29b1c29897
font_01_sfnt_off0000f4eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4EB 11288 bytes
SHA-256: 7ba461125e1d26ca2dc1c157a2bb5a3f6004ace96214088369fc858ddfa6c995
font_02_sfnt_off00010f39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F39 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1