Malicious PDF — malware analysis report

Static analysis result for SHA-256 814be87f59aaf145…

MALICIOUS

PDF

81.8 KB Created: 2021-09-19 21:37:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 24138b8fb38ac4548ff2188b16cce0c0 SHA-1: 21903951dbe5d206c5a5c4cfabb14586fecca189 SHA-256: 814be87f59aaf14555fcf21ab2e8c64ee74854bec64aab0d8a8afeb79e0045df
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS platforms. The presence of numerous PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM firings suggests a phishing or malware distribution campaign. No scripts were extracted from this sample, but the embedded URLs are the primary indicators of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://allytemp.ru/uplcv?utm_term=android+change+message+notification+sound PDF link annotation
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613e0f18ae7aa---60835380309.pdfIn PDF document text
    • http://eurekaelearning.com/upload/news/file/22987081311.pdfIn PDF document text
    • https://hazeloyun.com/calisma2/files/uploads/baguwezikuradiwekel.pdfIn PDF document text
    • http://pinzimoniofiumicino.eu/userfiles/files/90313259598.pdfIn PDF document text
    • http://samuiluxurytravel.com/Uploads/file/tuxarunoromiraju.pdfIn PDF document text
    • https://marugame.hk/editor_upload/file/18020835418.pdfIn PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614216f432e54---petibuwol.pdfIn PDF document text
    • http://mientaytourist.com/uploads/files/38406149100.pdfIn PDF document text
    • https://dongphuchuytai.com/upload/files/gomotodotepe.pdfIn PDF document text
    • http://scouttautomotive.com/editor_uploads/system/files/difupiripuzakafoni.pdfIn PDF document text
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/161324863a950c---38372317640.pdfIn PDF document text
    • http://pomelieagency.com/userfiles/files/90106398270.pdfIn PDF document text
    • http://chinajessie.com/seadata/data/uploads/img/file/163113553490.pdfIn PDF document text
    • https://farmacieitaliane.com/documenti/file/nujigeki.pdfIn PDF document text
    • http://www.addvanceo.info/userfiles/files/wawepege.pdfIn PDF document text
    • http://burragebrothers.org/demo/jolie/beta/userfiles/files/tolonujetaro.pdfIn PDF document text
    • http://factblogs.com/uploaded_files/userfiles/files/95744354882.pdfIn PDF document text
    • http://karate-talence.com/newsite/userfiles/files/rimawazojekevoleritif.pdfIn PDF document text
    • https://discovercefalu.com/_data/images/file/69617611999.pdfIn PDF document text
    • https://partroyfuneralhome.com/partroy/assets/file/38277651762.pdfIn PDF document text
    • http://omni-links-europe.com/images/blog/file/wamezokawumeperabawoxodu.pdfIn PDF document text
    • http://studiotecnicodavico.eu/userfiles/files/vulige.pdfIn PDF document text
    • 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_off0000d761.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD761 19056 bytes
SHA-256: 82e44abe20800d3bffa016ddd56f58560fbdd10a1ff7bb5022fd5665446e35c7
font_01_sfnt_off0001083f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1083F 10960 bytes
SHA-256: 34515b6bd7667385935f8f6312bc1cf7acfd2af5470a27e0b56748b051efd93c
font_02_sfnt_off00012158.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12158 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1