Malicious PDF — malware analysis report

Static analysis result for SHA-256 b51e9b586f1ebe26…

MALICIOUS

PDF

81.0 KB Created: 2021-07-07 03:24:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e63a604f360e19aeecbac5f34e4fbb7a SHA-1: be76d67885626fa0cdbb9e3c0ec16b06d40ef7f4 SHA-256: b51e9b586f1ebe26890f78bcc7d35a6481ba3a4212aff63da8105e6831323d39
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links pointing to external websites, many of which are hosted on compromised WordPress installations or disposable domains, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are consistent with a malicious PDF dropper.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

Heuristics 6

  • 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.
  • 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://pistant.ru/uplcv?utm_term=most+commonly+used+language+in+the+world
    • https://regeneracion-capilar.com/wp-content/plugins/super-forms/uploads/php/files/73ebaaffdb214a53eaa81e685e1ed01a/zesozivazofezosos.pdf
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/6ul0is48u23g0hi4inrqetbild/nuzimizitawutuluz.pdf
    • http://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/160ada5528ce8a---pigelegojiduxidubowane.pdf
    • https://www.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/4079cfc01ab3d3c55c47122036e47a15/93145573116.pdf
    • http://banphimchuot.com/userfiles/file/81744498209.pdf
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608ea1f260b61---lapik.pdf
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/5d44c2055de7d247227345ba28fa017d/rowutixalax.pdf
    • http://aaykpn.com/uploads/editor/files/59913031952.pdf
    • https://www.freshstartdigitalmarketing.com/wp-content/plugins/super-forms/uploads/php/files/ca5d82ce37dd52e9606fe40114e92099/zofok.pdf
    • http://szentdorottyapatika.hu/files/43061419182.pdf
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/160981b61c9996---70446525170.pdf
    • https://hitpoint.tw/userfiles/file/vemovinojev.pdf
    • https://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/cd4eee7bfcb5ccdde7d26eee871d50c1/fotovun.pdf
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160847a7632097---misuzavude.pdf
    • https://torbay.ru/images/uploads/file/vanazimimefunerabi.pdf
    • http://teaandtiarasottawa.com/clients/e/e8/e8f54e69a7463df9fd0adff13cd8e90f/File/55877327097.pdf
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/16071b6ad42b14---sosub.pdf
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d5114fef8e2---nekijugorajesarusiwipa.pdf
    • http://zbraneklapka.cz/ckfinder/userfiles/files/jajak.pdf
    • https://kisikana.hr/userfiles/file/zuwileruragukuk.pdf
    • https://przyklejki.pl/userfiles/54653820572.pdf
    • https://arendic.cl/files/wajifezogovexo.pdf
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076fe2a8c9f5---zozusogijometeku.pdf
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/8484565251f8fe532e8f86823650670b/gukepitumobisuxor.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_off0000d716.bin
dc525a9d5bfcd2ea8092aedcae8db1a927b35803e360759d04f0b76ed1714f21
pdf-font-stream PDF embedded font (sfnt) at offset 0xD716 16940 bytes
font_01_sfnt_off00010310.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10310 16792 bytes
font_02_sfnt_off00011b27.bin
0595b61b74f7b6ebe0cd1d0f4bf7c68f8d75d8fdccaf506194d98c12b46b9bb0
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B27 11112 bytes