Malicious PDF — malware analysis report

Static analysis result for SHA-256 883d6fa80e0ba938…

MALICIOUS

PDF

104.5 KB Created: 2021-07-06 05:43:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1bdf1dee6151ea7d677f16eace3692f4 SHA-1: 3749ec94634787287dda9310d066c123eef5f02c SHA-256: 883d6fa80e0ba9381cdd675a86dc9f2e08182edd7a84ae5db990f363ac41f996
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of external links, many pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the nature of the link farm and the detection results point towards a malicious document, possibly leveraging embedded JavaScript for redirection or exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://crysiq.ru/uplcv?utm_term=total+skin+layers
    • http://ebiocell.com/uploadfile/file///2021061720220193.pdf
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160a0db75853c4---tipuxegulorajiporojimixa.pdf
    • http://x-site.by/upload/editor/files/vusebabidomifum.pdf
    • http://nutronicltd.com/userfiles/file/39306024446.pdf
    • http://shs1977reunion.com/clients/41590/File/60613243864.pdf
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/1quhk96lbriclu22eo31im8tsg/tiwixevojorezo.pdf
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/92dd5d0489af7ad01dff1d0f383e5ac9/fogelebagadozakav.pdf
    • http://videoacceso.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be9b5ad45ac---22965706166.pdf
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b66ace9d5f6---lojikopuzed.pdf
    • https://alianzatours.com/imagenes/file/68753719623.pdf
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/hjeur95fhvbpnein2j3folcjhl/34773473196.pdf
    • http://cricalliance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cc641db383---39671034682.pdf
    • http://aylincinarli.com/fckfiles/file/donizabi.pdf
    • https://comtraining.cl/userfiles/files/56016694724.pdf
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/83a5d8f890182ac49252ff7fc002542d/59601413121.pdf
    • http://xn--49s538bo8ux8c.net/userfiles/file/58075528507.pdf
    • http://baschin-heizung.com/meineBilderAlbertGrundschule/file/tizasokufex.pdf
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/130e4e14bd79ab0d353d65ef3bd97f7e/76015480066.pdf
    • http://winecellarkeeper.com/ckfinder/userfiles/files/66088203392.pdf
    • http://emeat.ru/var/files/57013264710.pdf
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/e8efaab4239908bcf3d4dc3d4e0624ee/wofitewiwu.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_off000131ee.bin
7d4d1ca167c720cd44189c3843e4161713503161a8f43aaecf60f2fe220c10ca
pdf-font-stream PDF embedded font (sfnt) at offset 0x131EE 20284 bytes
font_01_sfnt_off0001647c.bin
70be6c3c118cb53b8f35a2dbca0b3d454e921b101efde676006023d8bc664b3d
pdf-font-stream PDF embedded font (sfnt) at offset 0x1647C 10272 bytes
font_02_sfnt_off00017bc6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x17BC6 16792 bytes