Malicious PDF — malware analysis report

Static analysis result for SHA-256 c670495f3c9382e2…

MALICIOUS

PDF

88.1 KB Created: 2021-06-26 06:08:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-07-10
MD5: 2edcd03c0b3e6c3bcbc1cb4d05b003ed SHA-1: 1156a1ec5b34343bd493717d6f3e6bbd3a7b5963 SHA-256: c670495f3c9382e23b7a2c868c934d074fc5e3dfa6f43c3eef4e82dc2ea8868a
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to distribute malicious content or conduct phishing. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the heuristic findings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://www.dartmusicfestival.co.uk/wp-content/plugins/super-forms/uploads/php/files/6b9ac89acc3d0050195de1a24b781ba9/disijixip.pdf In PDF document text
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/20ffl7d1a778a9f792mlrf6oo9/86061191528.pdfIn PDF document text
    • https://www.explosivo.gr/wp-content/plugins/super-forms/uploads/php/files/0fcd0d08af67ae55790e3c4c89f39b5b/50682997125.pdfIn PDF document text
    • http://ros-grad.ru/fck_editor_files/files/35303779766.pdfIn PDF document text
    • https://cissud.com/uploads/ck_editor/files/10885764103.pdfIn PDF document text
    • https://terravistahometeam.com/wp-content/plugins/super-forms/uploads/php/files/841d681df20863b0fcc0691a51a09d5e/69825574844.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9a834f297a---30554453954.pdfIn PDF document text
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c063052109---81417776964.pdfIn PDF document text
    • https://www.varishastalari.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074392a73944---bakinopegomatiwiweta.pdfIn PDF document text
    • https://tomas-music.com/contents//files/27175611634.pdfIn PDF document text
    • http://jyjwqj.com/uploadfile/file///2021052913024934.pdfIn PDF document text
    • http://scantech3d.com/files/52133812100.pdfIn PDF document text
    • http://yer-krasnodar.ru/ckfinder/userfiles/files/24850074415.pdfIn PDF document text
    • https://usdcp.jp/user_data/userfiles/files/26469053192.pdfIn PDF document text
    • https://juvelyrikoscentras.lt/Files/file/jakovizetelikazis.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160c08c9131162---zowebugexumuzomi.pdfIn PDF document text
    • https://www.ideaklinik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b665869026---ginapowuloxizate.pdfIn PDF document text
    • http://lesen-und-schenken.de/userfiles/files/82774223369.pdfIn PDF document text
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083c2253755b---239090002.pdfIn PDF document text
    • http://avtoarka.ru/wp-content/plugins/super-forms/uploads/php/files/24768bcac6ffe953d37bb68f320c832e/tupal.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1609fad9474c48---70880987585.pdfIn PDF document text
    • http://aldo-ins.com/userfiles/file/15317367972.pdfIn PDF document text
    • http://sanga.asia/userData/board/file/kodakipilolinubevojafi.pdfIn PDF document text
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0a1519a9d2---lenes.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=feelings+that+start+with+hPDF link annotation
    • 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_off0000f963.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF963 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001117a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1117A 10332 bytes
SHA-256: 27407abcd9a06e0f3dddef8250bc10ce33238044f192b4665867a7dcb6c72115
font_02_sfnt_off000128bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128BF 16480 bytes
SHA-256: 517be35cd33b6a5327b0f5af7d912bb7cc0fc61c7cbd85abd8aa75c3db8cc20f