Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b42e89f8fe511c5…

MALICIOUS

PDF

91.9 KB Created: 2021-09-08 18:25:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: ea8c064800f7548fc899822a7f6f64d7 SHA-1: 3a0877d43ab99cc26432aabbf7ca8b6da2a27005 SHA-256: 5b42e89f8fe511c57dfbc36fb357400b04ee5e5e4dd608b42221e72ced498db2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF that contains numerous links to external websites, many of which appear to be hosted on compromised or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of PDF link farm heuristics suggests the document's primary purpose is to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

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 https://laborke.ru/uplcv?utm_term=patriotismo+e+nacionalismo+pdf PDF link annotation
    • http://hoya-system.com/uploads/files/202109071058086855.pdfIn PDF document text
    • https://traffictkt.com/viking1/uploads/files/jokirodaxiburimowemeni.pdfIn PDF document text
    • https://biocoop.legreniervert.fr/ckfinder/userfiles/files/32703353089.pdfIn PDF document text
    • http://tgtech-auto.com/userfiles/file/27531698048.pdfIn PDF document text
    • http://terralis.eu/catalogue_dynamique/file/23833292422.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612faa00493c2---38065487977.pdfIn PDF document text
    • http://jr.ac.th/ckfinder/userfiles/files/97149699039.pdfIn PDF document text
    • https://rmduncanrealty.com/userfiles/files/jorowoluzusoxapom.pdfIn PDF document text
    • http://spbi.cz/res/file/vejepusulivoginut.pdfIn PDF document text
    • http://tubietelbar.hu/uploadfile/vuferusonujupanukod.pdfIn PDF document text
    • https://cylinder96.ru/admin/ckfinder/userfiles/files/pobebokigavofisu.pdfIn PDF document text
    • http://hejia-ele.net/upload/98862734635.pdfIn PDF document text
    • http://upnbkk.com/file_media/file_image/file/43853043482.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613052ea249e7---24713072343.pdfIn PDF document text
    • http://autoscuolapezzano.it/userfiles/files/setukodidukikojexawu.pdfIn PDF document text
    • https://tideandtigers.com/ckfinder/userfiles/files/27507732664.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612ed6e55ecc3---99054759804.pdfIn PDF document text
    • https://bawauang.com/contents/files/sefagixeded.pdfIn PDF document text
    • https://mgc.to/sites/web/upload/files/92875242996.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/1613182ee25084---kupulaxevopedutaniwesipe.pdfIn PDF document text
    • http://bjdfszwy.com/filespath/files/20210904215139.pdfIn PDF document text
    • https://mediaget.com/userfiles/files/4824055556.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_off0000f9c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9C7 10780 bytes
SHA-256: 4f8d64bc232f5373784f8e8346f08fb4603db9fe1ee3a63a517f66e4e121ac5b
font_01_sfnt_off00011298.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11298 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012aaa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AAA 21116 bytes
SHA-256: bd85cf494c0d85928379ac92c03e344150de1ab521361a28a444373b81c1b761