Malicious PDF — malware analysis report

Static analysis result for SHA-256 8bf4c4ba492496d5…

MALICIOUS

PDF

87.5 KB Created: 2021-07-05 07:26:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 16c7898f7fcee7961a8541b4242d7a51 SHA-1: 693170e7a2df7e5796b09fd7318b25fe6d728c08 SHA-256: 8bf4c4ba492496d5bb207d76fa8557c199a85df9ded134f136806656fe817f2d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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=picking+a+guardian+for+your+child
    • http://muzeumostrowiec.pl/obrazy/file/jarafi.pdf
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ca2eb86eade---68493922942.pdf
    • http://firegallery.ru/img/upload/27295543731.pdf
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160713dc5bb8dc---bidevawavuvodufelo.pdf
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/4ofir8gn9l237gknrp1i87h2ir/12471661478.pdf
    • https://machnhaduong.com/images/uploads/files/sunoxe.pdf
    • http://sgd42.ru/userfiles/file/89488963382.pdf
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb0932a6480---58540613423.pdf
    • https://beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/b40aaca0a1e236ea201a03065c13c513/vutivemaxiwedukulubaz.pdf
    • http://alpha-th.com/userfiles/file/7721457883.pdf
    • http://chhsclassof70.com/clients/1/1f/1f6d1b94cf555b90b9f410dfa82aea5f/File/felidumu.pdf
    • http://esenkardeslerinsaat.com/resimlerfiles/sigetuvafonumebirelinoza.pdf
    • https://cardion.dk/gfx/fckimages/file/68414179808.pdf
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/56nslg3u8t7id4bs1c4vr86v14/semogawezubanumuxize.pdf
    • http://avanti-kuhni.ru/upload/files/zuxomotetuxewaj.pdf
    • https://bohemiamaestro.com/webpagebuilder/ckfinder/userfiles/files/9115254412.pdf
    • http://effektfilm.de/files/file/jefiwulopu.pdf
    • http://africanhairbraidingsalon.com/userfiles/file/tojivedewi.pdf
    • http://cerezolorente.com/files/cerezolorente/_repo/file/wivolexibovuxita.pdf
    • http://alibabashipping.com/userfiles/file/28167072678.pdf
    • https://www.oneirishrover.com/wp-content/plugins/super-forms/uploads/php/files/da5a71c41927653150114f67da1c2718/19999431403.pdf
    • https://www.kalirich.com/wp-content/plugins/super-forms/uploads/php/files/hrkq08tiv0f4260l4coa82t0c5/897667809.pdf
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160980e4c11bfa---62806955120.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_off0000f496.bin
6c70a2891a0bc65e91c9124f6ab185b92ab7120e2b9909cd224d1f2480f1426a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF496 16916 bytes
font_01_sfnt_off000120aa.bin
1094d81507208fcd415fa7ca050d024fc4fb568534c8abe9f69f40ba7c03ef7c
pdf-font-stream PDF embedded font (sfnt) at offset 0x120AA 10664 bytes
font_02_sfnt_off000138d2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x138D2 16792 bytes