Malicious PDF — malware analysis report

Static analysis result for SHA-256 15a6f7cba3356e67…

MALICIOUS

PDF

80.8 KB Created: 2021-09-12 19:21:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 951c2bfcd56465bc2114615a1818e8d6 SHA-1: 8bfabfe5cb9f75216b2c204a3a2af23d3b9c18e9 SHA-256: 15a6f7cba3356e6754d0cf935aea8d00abf5263dcdeff5dc85c439282ad5767c
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to compromised WordPress uploads and other disposable hosting, likely to distribute further payloads. The 'SE_PASSWORD_ARCHIVE_LURE' heuristic suggests the document may instruct the user to open a password-protected archive, a common tactic to bypass gateway security.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://theofficefurniturestore.com/ckfinder/userfiles/files/dexitidoxiwimikopefita.pdf In PDF document text
    • https://eventaipei.com/upload/files/26089147485.pdfIn PDF document text
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/vku51dc3o320fmdg7qs0hhhclc/woganitekajasizojabipop.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613264caec1e7---givuzimapofibiral.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1613dcd7c114c9---pipijazanexebofobumozawom.pdfIn PDF document text
    • http://nktrading.qa/file/files/vuzetakebaredapoxutajovu.pdfIn PDF document text
    • http://www.multigacos.com/admin/uploaded/fck/file/xavisugapo.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f85034cd52---2035276487.pdfIn PDF document text
    • https://intersensor.ro/v2011/Files/fck_upload/file/3876905375.pdfIn PDF document text
    • https://chungcungoaigiao.vnpec.xyz/uploads/files/71971959262.pdfIn PDF document text
    • https://menokatea.in/ckfinder/userfiles/files/44930430718.pdfIn PDF document text
    • http://9jamail.com/FCKeditor/editor/filemanager/connectors/userfiles/file/voraj.pdfIn PDF document text
    • https://er-cardiff.com/eurostyl/photos/file/76801158424.pdfIn PDF document text
    • https://faceless.me/userfiles/files/9561322296.pdfIn PDF document text
    • http://eugensa.lt/app/webroot/uploads/userfiles/files/kividujubozerazider.pdfIn PDF document text
    • https://shevtsov-art.com/uploads/files/72203310710.pdfIn PDF document text
    • http://ultrabeauty-ff.ru/userfiles/file/wosetujevozenalilo.pdfIn PDF document text
    • https://cualuoihoanmy.com/uploads/userfiles/file/sunap.pdfIn PDF document text
    • http://candybeauty.vn/upload/files/65168292794.pdfIn PDF document text
    • https://5udua.com/contents/files/fegumudifi.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ead9a9147c---82601116344.pdfIn PDF document text
    • http://grawerlik.pl/userfiles/file/44979701956.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/b5d51af19f50b46a7cec96aafad944d6/39156955334.pdfIn PDF document text
    • https://onutglen.com/caningest/images/file/zugerijiginisodijaxawiru.pdfIn PDF document text
    • https://tasteadmin.com/ckfinder/core/connector/php/custom/wysi_uploads/files/gadakoroki.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=how+to+unlock+a+locked+androidPDF 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_off0000db16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB16 16212 bytes
SHA-256: 07cb7183a7db3fe243a7618e937c4a864d5656ccee12162d5121d21b0e9388e9
font_01_sfnt_off00010503.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10503 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011d1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D1A 10464 bytes
SHA-256: c1aa9d3fd0ab8bffe0b1dfa691e5e4d5de29bf267e2586d20775a2c494926302