Malicious PDF — malware analysis report

Static analysis result for SHA-256 d52b6418e9afccd8…

MALICIOUS

PDF

71.1 KB Created: 2021-10-04 18:11:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 7603db9905cdbb6e698aac22c893c160 SHA-1: 8201c2ef298609653a517749df85dccb50a0b79d SHA-256: d52b6418e9afccd847825f5b6fb77a0dcfa887f94885b67cd1117d77d4d7f3d4
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It functions as a link farm, with numerous embedded URLs pointing to various domains, including those hosted on compromised WordPress sites. The 'utm_term' parameter in some URLs suggests a potential phishing or SEO manipulation tactic to lure users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://infrive.ru/uplcv?utm_term=data+communications+and+networking+5th+edition+solutions+pdf PDF link annotation
    • https://study-abroad-travel.com/ckfinder/userfiles/file/xajapogugitiwepiw.pdfIn PDF document text
    • https://anukulagrotech.com/userfiles/file/97961358471.pdfIn PDF document text
    • https://www.icicle-mountaineering.ltd.uk/ckfinder/userfiles/files/82418664755.pdfIn PDF document text
    • https://imaggu.com/ci/userfiles/files/20544836203.pdfIn PDF document text
    • https://prcomponents.com/ckfinder/userfiles/files/73752264397.pdfIn PDF document text
    • https://dragonexpressml.com/userfiles/files/punuxozej.pdfIn PDF document text
    • http://minhledtran.com/luutru/files/79993650907.pdfIn PDF document text
    • http://mobiliteit.nu/files/kuxifosile.pdfIn PDF document text
    • http://anabakorea.jp/userfiles/file/pebopujovaxet.pdfIn PDF document text
    • https://nguyenhungstone.com/uploads/image/files/17847698325.pdfIn PDF document text
    • http://ackerviewguesthouse.com/userfiles/file/49227639232.pdfIn PDF document text
    • http://msslink.ru/userfiles/files/42951827867.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/07d7ce1a8c672cac74be3de16f6a516b/61689147143.pdfIn PDF document text
    • http://e3edu.vn/public/ckfinder/core/connector/php/connector.phppublic/uploadsfiles/wazogenofet.pdfIn PDF document text
    • https://tlkingatlan.hu/kepek/other/file/43539018058.pdfIn PDF document text
    • https://guruamardaspublicschool.com/userfiles/files/fowaxemotanako.pdfIn PDF document text
    • http://fullx.net/files/kibenepibumoritanirekaf.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/c8c498d150ccb22671082a73f15ce44f/jalepinuferu.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/1614f8269d0cb1---ronemimeb.pdfIn PDF document text
    • http://alompar.hu/uploads/content_files/files/46783106517.pdfIn PDF document text
    • https://aczv.fr/userfiles/file/36099020007.pdfIn PDF document text
    • https://nyig.com/files/file/69775893962.pdfIn PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613ff5ed35af1---xukix.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_off0000b490.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB490 11480 bytes
SHA-256: 482a7cf77c232086b7369264881cd41395e055d518cc7391d2ba2b27e11fc72e
font_01_sfnt_off0000cf6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF6B 15120 bytes
SHA-256: 6ddf79dc5ca3e257ff4843abbe12de1707697522c699e40e81338c6be0dd0452
font_02_sfnt_off0000f606.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF606 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1