Malicious PDF — malware analysis report

Static analysis result for SHA-256 f073a614c22027e2…

MALICIOUS

PDF

72.5 KB Created: 2021-09-12 05:55:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 2375f9068f3be37540da5f8897ab2697 SHA-1: 7fc4ad26baa409701aef25f1169bd7ab20a9af00 SHA-256: f073a614c22027e26f7d2cc0227ea47ec2ce153ad288d572f2a1cbf6b0b036f0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external links, many hosted on compromised or disposable domains, suggesting a link farm or phishing lure. The PDF structure and embedded URLs point towards a phishing attack, likely using a spearphishing attachment as the initial access vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://synerhu.ru/uplcv?utm_term=a+and+an+exercises+pdf PDF link annotation
    • http://botosani.ro/img/uploads/file/99187174489.pdfIn PDF document text
    • https://almentispharma.com/ckfinder/userfiles/files/42523538247.pdfIn PDF document text
    • http://newcityhk.com/userfiles/82263347841.pdfIn PDF document text
    • https://vialivonica.eu/userfiles/files/fafisurininazebotuf.pdfIn PDF document text
    • https://rippa.pt/files/file/61622761631.pdfIn PDF document text
    • http://timandlor.com/userfiles/file/zinasaxuf.pdfIn PDF document text
    • http://jeanchapleau.com/userfiles/file/10158043448.pdfIn PDF document text
    • http://geredekombiservisi.com/userfiles/file/bixovowozimevek.pdfIn PDF document text
    • http://boki.hu/editor_up/34446224421.pdfIn PDF document text
    • http://dyccpharma.com/upload/files/wasanexozuwosodexarab.pdfIn PDF document text
    • https://n-zvuk.ru/upload/file/wezibokotarixejuwad.pdfIn PDF document text
    • https://cs168.tw/upfiles/editor/files/rapukolotujilaxifebexa.pdfIn PDF document text
    • http://hillcrestneighborhoods.com/userimages/nulukewogizejebepi.pdfIn PDF document text
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/00aa92ae166951e64a56078f1164cbeb/50349391565.pdfIn PDF document text
    • http://akinmedical.com/uploads/file/29443158170.pdfIn PDF document text
    • https://jancsoalapitvany.hu/ckfinder/userfiles/files/rebigenupumukivomib.pdfIn PDF document text
    • https://sf-tfi-pgu.uz/wp-content/plugins/super-forms/uploads/php/files/ab41c1d3b6fe47164e546dd42c0b5516/75817977633.pdfIn PDF document text
    • http://belean.pl/userfiles/file/rigefenibi.pdfIn PDF document text
    • http://www.polni.si/Images/files/73713707732.pdfIn PDF document text
    • http://massimosusto.eu/userfiles/files/ligofapuf.pdfIn PDF document text
    • http://boxshop.mn/userfiles/files/96722614746.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/0549f645b53ed49a53080f4765fd7442/29752397128.pdfIn PDF document text
    • http://zhfangyuan.com/uploadfiles/files/3245242050.pdfIn PDF document text
    • http://www.jucadent.es/ckfinder/userfiles/files/46057078957.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134166db0092---35807606159.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_off0000bb17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB17 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d329.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD329 16220 bytes
SHA-256: 86b7a884635a7fae67abe3212cb1aa89bfd0a67a9d40043bb445b613c96329aa
font_02_sfnt_off0000fd14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD14 10432 bytes
SHA-256: b39679549981ffa1637474d56d9b85fc0cf5cdd8021b59cbcb6c8f9606381b23