Malicious PDF — malware analysis report

Static analysis result for SHA-256 8136f41b24ee9b7a…

MALICIOUS

PDF

89.5 KB Created: 2021-07-05 04:47:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 9f22fca5afaf8f91220b91ada6a7bab8 SHA-1: adf440c10e4752786d9bfce460de41d9c3b34266 SHA-256: 8136f41b24ee9b7ade577a8755e2f49534f7a06ac6186c3cf83462deae3caa5f
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 it likely exploits PDF vulnerabilities or serves as a lure. The document contains a link farm pointing to numerous URLs, many hosted on compromised CMS platforms or disposable domains, suggesting a phishing or malware distribution attempt. No scripts were extracted, but the presence of multiple external links and the nature of the heuristic firings strongly suggest an intent to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://mudrkanuch.sk/editor_uploads/system/files/55721643143.pdf In PDF document text
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/7e4cb0fc8dbd2501eec0a28d58996950/dazuwitesutim.pdfIn PDF document text
    • http://dush-kz.ru/uploads/fck/file/bamofunimis.pdfIn PDF document text
    • https://akproauto.com/nbloom/fckuploads/file/gunizidefewavukife.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160d82758dfb77---3810242318.pdfIn PDF document text
    • http://canevinclassof70.com/clients/6/6b/6b8b8ee0d314e59372afbcb75100d768/File/zosoxatobutor.pdfIn PDF document text
    • http://almar-bus.pl/userfiles/file/6945113767.pdfIn PDF document text
    • https://festivalecolo.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160bb1d18cdfd6---pulowaxemeximo.pdfIn PDF document text
    • http://www.zywawiara.pl/pliki/1663879671.pdfIn PDF document text
    • https://www.nexidia.it/wp-content/plugins/super-forms/uploads/php/files/19ad7d3c4e35809237ccd58b61d1b9b3/77015680125.pdfIn PDF document text
    • http://perlawarmii.pl/userfiles/file/vuzozow.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16081e258a6f1e---wuxolinatidazorinivi.pdfIn PDF document text
    • https://www.gasserbush.com/wp-content/plugins/super-forms/uploads/php/files/8cc6ffacafcd1e7e4ecea2f35c9ee9ad/saridoxamerilifumig.pdfIn PDF document text
    • http://aceonlinementors.com/userfiles/file/21889537319.pdfIn PDF document text
    • http://koreanhotpot.com/uploads/files/39294907233.pdfIn PDF document text
    • https://monacollection.ua/wp-content/plugins/super-forms/uploads/php/files/728cc1c25bb548ece5fbeac7fec24b05/relizawawele.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160aee4db5f7b6---nebof.pdfIn PDF document text
    • https://italvaping.com/file/77615634110.pdfIn PDF document text
    • https://summit-christian-academy.com/scauserfiles/files/pakawebododukuwuwe.pdfIn PDF document text
    • http://seasonsblinds.com/uploads/ckfinder/userfiles/files/darupupedifi.pdfIn PDF document text
    • http://meetburgerusa.com/uploads/files/gujopotikewaruxiwuvixid.pdfIn PDF document text
    • https://rmp-traueranzeigen.de/cms/files/14987167817.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=gambia+in+mapPDF 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_off0000fd49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD49 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001155f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1155F 9928 bytes
SHA-256: ac4ad69b80fc8ab7b91818fb80870c0b0d653e8954cac0a6218fd08ef4acd1f2
font_02_sfnt_off00012af3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AF3 17716 bytes
SHA-256: 7b0dac3f4900f3b773d826b272bdef903cb4009c67436f9b641ae37fa05dc1d4