Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc89d31c479de6d7…

MALICIOUS

PDF

83.6 KB Created: 2021-08-02 10:47:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 40918c6c9ad40ffcc7172e41d1bf4bbd SHA-1: 60b127ce45402e355493e308e2577b07c8ef13d1 SHA-256: bc89d31c479de6d72813f751eed911b6a0e8e16d873f58def1a0e8e5a6ea39dd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF contains numerous embedded URLs pointing to compromised WordPress sites and disposable hosting, indicative of a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and unreadable, providing no direct content-based clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://crewmak.ru/uplcv?utm_term=probabilidad+y+estadistica+para+ingenieros+6ta+edicion+pdf PDF link annotation
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c71ee60cf2---ragexigiwak.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/7t5tkt2qv9bpi7vububuqhg8p4/67315378742.pdfIn PDF document text
    • https://agrocare.ro/ckfinder/userfiles/files/jitolufugatukilogit.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/nijolikopesagibep.pdfIn PDF document text
    • https://fresh-cherries.com/ckfinder/userfiles/files/6821234922.pdfIn PDF document text
    • http://theettiaresmontreal.com/clients/f/f0/f03dfc1790708d0b03c48e9879ef2ea6/File/buzifomesupupopaf.pdfIn PDF document text
    • http://skiflogistics.ru/userfiles/file/kadojonow.pdfIn PDF document text
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/c8617bf629e42634fbddf48c17958313/kuleda.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160dbdcfcf3988---fupeviwumuzibak.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/uh7ht1d17ehrhq1qft5du8bthp/pepurevogugi.pdfIn PDF document text
    • http://axwelindia.com/uploads/99553128906.pdfIn PDF document text
    • https://gyn-koe70.de/obrazky/file/54460317312.pdfIn PDF document text
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/3505dc22e379482cadac03c5725d1be5/wilujutubuligazo.pdfIn PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/678fb360c1d69f19ffffa59a10e66782/nugak.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3fc8081731---74167409588.pdfIn PDF document text
    • http://ayhancevik.com/images_upload/files/95279483775.pdfIn PDF document text
    • https://chris-arnold.com/userfiles/file/faviremewemamu.pdfIn PDF document text
    • http://aceonlinementors.com/userfiles/file/nexawiwofonezojofojofoxi.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ed8b615a2d7---58293493295.pdfIn PDF document text
    • http://www.deopendeur.org/imgUser/file/24464835168.pdfIn PDF document text
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606cfc49199ac---sozuvijarubexe.pdfIn PDF document text
    • https://clinicscrm.com/img/files/74713753249.pdfIn PDF document text
    • https://premium-house.uz/images/file/90371306036.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076217da3b6a---sabupunajajegi.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_off0000d9f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9F1 11220 bytes
SHA-256: 1c7729f3e32f9de48a7ee7ae67b52a4e0bdce52ce81cff22417a0d1eff9163b3
font_01_sfnt_off0000f3ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3EF 19332 bytes
SHA-256: f56f9b19e8fdde98f036752b0f97b9ada724af574c94726058ca80bda5fb9ae3
font_02_sfnt_off0001260b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1260B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1