Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b1c11d306b45a75…

MALICIOUS

PDF

79.0 KB Created: 2021-09-18 18:07:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 1b48ce3d45fb68ba54d413c34d8f22ba SHA-1: ad85331178f9741a0a02b94f4b6cb1829ed78bb3 SHA-256: 5b1c11d306b45a755a4ddc4be9efa27fb791ae46cc39d81b45d1c7c5c25a8ac8
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to lure users to potentially malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://cructi.ru/uplcv?utm_term=how+to+unblock+your+iphone PDF link annotation
    • http://arisutour.com/ckupload/files/ropuzamofiruravasobaforiv.pdfIn PDF document text
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/161327e2ae6b1e---59575356806.pdfIn PDF document text
    • http://evrokomplekt.ru/userfiles/file/5196742723.pdfIn PDF document text
    • http://jagatjyotischool.org/jagatjyotischool/userfiles/file/7967534728.pdfIn PDF document text
    • https://gifarlcm.com/upfiles/editor/files/27535808562.pdfIn PDF document text
    • https://khonggiansangtao.com/platformecom/img/upload/file/tuguzajinunepi.pdfIn PDF document text
    • http://chinajessie.com/seadata/data/uploads/img/file/163125414231.pdfIn PDF document text
    • https://speedwayinfo.hu/uploads/file/31010585171.pdfIn PDF document text
    • http://cycling-software.com/files/file/70203873879.pdfIn PDF document text
    • http://www.de.ruben.pl/ckfinder/userfiles/files/lusigivovenegewamesipef.pdfIn PDF document text
    • http://abwplazaview.com/uploads/files/bafidunibagikesupedonafik.pdfIn PDF document text
    • https://takipcisec.com/calisma2/files/uploads/gatumuxefatarutopijak.pdfIn PDF document text
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/43d5461326c0f1ee53f4c839c4946a4f/vibozorujorarilulu.pdfIn PDF document text
    • http://escuelasfutbol8.com/docs/files/96174597294.pdfIn PDF document text
    • http://dreesmann-foto.de/userfiles/file/28183414035.pdfIn PDF document text
    • http://www.yeosung21.or.kr/ckfinder/userfiles/files/1631476582.pdfIn PDF document text
    • https://dauglita.lt/components/com_mijoshop/opencart/image/data/files/nazitazasi.pdfIn PDF document text
    • https://bishopsalamatkhokhar.org/userfiles/file/83297562417.pdfIn PDF document text
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/16132980b4d7b5---205194347.pdfIn PDF document text
    • https://aep-tc.com/cache/fck_files/file/30746481432.pdfIn PDF document text
    • http://andreuma.madteam.net/ckfinder/userfiles/files/sininokezugiwatuxotapopen.pdfIn PDF document text
    • https://woft-dining.com/webroot/editor-uploads/files/viwufikaba.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_off0000d074.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD074 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e88b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE88B 10664 bytes
SHA-256: 254b43a44dfb63852ff6f6fabbcd8928758cf8b838964b47929c993332bf7a2e
font_02_sfnt_off000100b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100B6 17716 bytes
SHA-256: 18fb34785d177eedf60e4abf011055f624a7e1bba50d9001cc13904af8000285