Malicious PDF — malware analysis report

Static analysis result for SHA-256 99a7e87ef684c427…

MALICIOUS

PDF

82.9 KB Created: 2021-09-12 21:56:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ae7e49bd4f4ec90678c213a76509b07a SHA-1: f4daa1303f39e5dfe290635ca0cbd46e4e28f859 SHA-256: 99a7e87ef684c427a4c5a9c3123e1cc061ca4a6016a6520bd013069c428ce6b2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS upload storage. The presence of numerous links on disposable hosting and the use of 'utm_term' parameters suggest an attempt to manipulate search engine results or track user engagement for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://wastran.ru/uplcv?utm_term=lord+of+the+rings+trilogy+watch+online PDF link annotation
    • https://biholka.cz/uploades/userfiles/file/sekakejezakugebexap.pdfIn PDF document text
    • https://giaiphapthietke.vn/media/file/files/13209070991.pdfIn PDF document text
    • https://bawauang.com/contents/files/33201832635.pdfIn PDF document text
    • http://alpinist.store/sribati/editor/uploadfiles/76670466791.pdfIn PDF document text
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/grannc6jiel2rofmdtviudt2gh/baniniwovuriveluvi.pdfIn PDF document text
    • https://horizontire.com/userfiles/file/nipugonuvo.pdfIn PDF document text
    • http://krzysztofmalec.pl/gfx/fck/file/rupudepufudagubezawavezo.pdfIn PDF document text
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/3535b8cf09a17d32fab8a40194839aa9/jukenutigapaxobijana.pdfIn PDF document text
    • https://skatrip.com/basefile/skatripcom/files/6775865407.pdfIn PDF document text
    • https://viettincapital.vn/upload/files/91970304025.pdfIn PDF document text
    • http://ottotech.center/userfiles/file/vawaxuniwi.pdfIn PDF document text
    • http://kperrylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zejesulodebabawipetawalu.pdfIn PDF document text
    • https://nedimgame.net/calisma2/files/uploads/54438597459.pdfIn PDF document text
    • https://bawaniint.com/ckfinder/userfiles/files/gebuve.pdfIn PDF document text
    • https://detector-billetes.com/Imagenes/file/wodalekodevez.pdfIn PDF document text
    • https://speculatio.in/ci/userfiles/files/66872359055.pdfIn PDF document text
    • https://noriupapildu.lt/ckfinder/userfiles/files/70428808050.pdfIn PDF document text
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613497a5c5b34---kuzulumim.pdfIn PDF document text
    • http://www.ortodonciaelisafarache.com/ckfinder/userfiles/files/ruwakumojuzuluzigo.pdfIn PDF document text
    • https://mai-avto.ru/upload_files/file/xesijinixuk.pdfIn PDF document text
    • https://petala.gr/userfiles/file/fegurove.pdfIn PDF document text
    • https://rowadalbyt.com/userfiles/files/tivawaxekivoxatijokozabar.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_off0000df4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF4D 10912 bytes
SHA-256: 81b7c45ce9a2fcec5c00b6e337bd54042c43db87ac74f78dd6f5acecb757ddda
font_01_sfnt_off0000f85f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF85F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011071.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11071 17504 bytes
SHA-256: 067fd635e551b1d2da9550c08a6be0cb0ea55772885417c0b16ea9258156306f