Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4fca20bcece7948…

MALICIOUS

PDF

76.1 KB Created: 2021-07-04 23:26:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d57547bccd0c1fd499401b548eba5db5 SHA-1: 0263bed4428659c0352ad2d41f5ceaed879944c4 SHA-256: b4fca20bcece7948e0585ae4452d6e4ceb77001fa1f29c64f536060744313d25
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous embedded URLs pointing to compromised WordPress sites and disposable hosting. These links likely lead to phishing pages or further malware downloads, aligning with a spearphishing attachment attack pattern.

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.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608691c027679---geberaxeguxega.pdf
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/ab1ccb479b7ceab1d1743818ddc1e403/xiwatepes.pdf
    • http://robertsrucker.com/clients/7/7f/7f5ecd1287ec2152c36a7dc1808edcbf/File/purafuv.pdf
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/e090f837875be83e9d55dd9df8a04ece/6593553357.pdf
    • https://ludifrance.fr/userfiles/file/berunezosasexafu.pdf
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/mu3bqhibq70bnpekrtntsfsb66/92853337233.pdf
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bad7bacaf9---77766708867.pdf
    • http://arci-mp.fr/admin/File/57236424359.pdf
    • https://equantumconsulting.com/files/files/nelepabik.pdf
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/slgfsi6kfs6f599j9sv36kt57v/42565546908.pdf
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/160865550dff58---nixevukesaludizeramuj.pdf
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/7d543016cfe3bad6ed7db57a75fee168/93523090905.pdf
    • https://ilc.ua/wp-content/plugins/super-forms/uploads/php/files/sg3ttr63uioshaotuoled0def3/naribivuzovanevofapogewel.pdf
    • http://www.dj-csnl.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607a18d144823---keruwurewiwememudibiveb.pdf
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160da6b59a165f---53069299214.pdf
    • http://tragiaocolamsapa.com/userfiles/image/file/79385963228.pdf
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608eb956de498---8254349282.pdf
    • https://www.rowtheerne.com/wp-content/plugins/super-forms/uploads/php/files/d3fd029d5f27af3fa644beeb2ea0a3b2/dikemutegep.pdf
    • http://samuiluxurytravel.com/Uploads/file/susewoxuxuxaki.pdf
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7335c165a3---60834525936.pdf
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/16090b1f83394d---zusepifosagoranesinet.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/56a83siprgv1cm0meebqp3evhd/90392185408.pdf
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160cc5fc7b2cf2---dopomekiriz.pdf
    • https://www.apollopowersystems.com/wp-content/plugins/super-forms/uploads/php/files/099499210c8868805092ee34a1ae9e8e/dimexewameliravigotegobom.pdf
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae19a70d81a---10238818652.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=bank+overdraft+meaning+in+accounts
    • 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_off0000c7e2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC7E2 16792 bytes
font_01_sfnt_off0000dff4.bin
874d9bbf2fc0514090048720ee44ea299181f2058d4d84347b28468bc295228c
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFF4 15900 bytes
font_02_sfnt_off00010922.bin
006ad7c1b3be24b3e0bb2819d8299ebb3575cfcd7e6cb7d8ad5aedfdf648e2c3
pdf-font-stream PDF embedded font (sfnt) at offset 0x10922 11084 bytes