Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a021cbd2582a80f…

MALICIOUS

PDF

77.1 KB Created: 2021-09-03 09:48:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 1d13f32c84782fd8ac095f206fdfbe11 SHA-1: 9f4913389ee8f4e4b78f3d63d372ffd3849316a9 SHA-256: 8a021cbd2582a80fc69192579997ed6979c4806c7525f60ebfd3bd25a8d6d293
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many hosted on compromised CMS platforms or disposable domains, suggesting a link farm designed to redirect users to malicious content. While no scripts were explicitly extracted, the PDF format itself can embed JavaScript, and the heuristic 'ML_NYX_PDF_MALICIOUS' suggests sophisticated malicious capabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9934

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 http://fine-cottage.ru/userfiles/files/30106953547.pdf In PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8ccf3b0f5a---xapabulejifegemigironavo.pdfIn PDF document text
    • https://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/c5087e9c4b48f9893a6b0bb49c6a5149/33313423918.pdfIn PDF document text
    • https://greenbins.ca/ckfinder/userfiles/files/66628223403.pdfIn PDF document text
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/e5505cab7c1a62e063013a530fe429cc/kokejokibasamuzok.pdfIn PDF document text
    • https://www.jakketoes.be/ckfinder/userfiles/files/69463331591.pdfIn PDF document text
    • http://currycornersugarland.com/admin/images/file/54164568376.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160aa29a5a2947---34392529157.pdfIn PDF document text
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a23972718d7---93128143792.pdfIn PDF document text
    • http://ahcxdq.com/uploads/file/070352346723.pdfIn PDF document text
    • https://maugli24.ru/wp-content/plugins/super-forms/uploads/php/files/40d33bdd6b6e06ea03d48ca74628147d/remipitemuxujibuva.pdfIn PDF document text
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160c5d9ffac452---fofegebesagofejabefirofo.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ab62fed8b9e---mitosexiwawelibajopo.pdfIn PDF document text
    • http://geometrabottero.it/userfiles/files/60087979378.pdfIn PDF document text
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/271b69ea48784d027ae40d7a9d19e695/73898819704.pdfIn PDF document text
    • https://local-atlas.ru/userfiles/files/18295660598.pdfIn PDF document text
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/ou5h7nmerembj6o9ekgt9v0t71/632316776.pdfIn PDF document text
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/20302f68ba4cfe01f4831ade7a601afa/niwigabetomi.pdfIn PDF document text
    • https://vegan-eshop.cz/data/file/27447035296.pdfIn PDF document text
    • http://pujcovnanaradi-tvarozna.cz/userfiles/files/tonewudetigavoj.pdfIn PDF document text
    • http://palirna-frydek.cz/uploaded/file/87682974237.pdfIn PDF document text
    • http://pension-erlkoenig.de/img/editor/file/lalifupemepuxamitukebimam.pdfIn PDF document text
    • http://csc0451.com/userfiles/file/20210622163451_vf8mz4.pdfIn PDF document text
    • https://netron.pt/app/webroot/media/files/9432462539.pdfIn PDF document text
    • http://doorsatyrau.com/ckfinder/userfiles/files/78332436284.pdfIn PDF document text
    • http://slstudio.it/userfiles/files/tibutimi.pdfIn PDF document text
    • http://cuathepvangohaiduong.com/images/ckeditor/files/51050237828.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=seguridad+juridica+pdf+unamPDF 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_off0000c6ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6AC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000debe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEBE 18564 bytes
SHA-256: d29e0f812eb1594ebc40c831c2edb24c0055c24879c078ea8eeb2a24cecc1f9d
font_02_sfnt_off00010ddd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DDD 10836 bytes
SHA-256: 8041ad11ff8f6253e13303c2cada9dc2dff7fb1e427343fcdfab7542bfe7ccaa