Malicious PDF — malware analysis report

Static analysis result for SHA-256 1550a5b955cfe9de…

MALICIOUS

PDF

76.0 KB Created: 2021-09-22 21:20:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 8fdab7cf82802d3508632aa98367f54f SHA-1: 8a6d423bae2a375cfc68fc1af4948bf2641c6fe8 SHA-256: 1550a5b955cfe9de2998530c0896f2de50a37d73128341a7beae0fa7c092cc46
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Phishing.Trojan' and an ML classifier indicating maliciousness. It contains numerous embedded URLs, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of these links and the overall detection profile strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://garglob.ru/uplcv?utm_term=star+wars+force+arena+play+store PDF link annotation
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16149c8f7daccb---66752401511.pdfIn PDF document text
    • https://polaria.cz/images/file/xumixef.pdfIn PDF document text
    • http://otczenacts.com/media/files/mojodobu.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/mqd44ohhfbv5bu50iiqj88uv8l/77203898024.pdfIn PDF document text
    • http://tw-echen.com/uploads/files/202109161058225963.pdfIn PDF document text
    • https://kaptenhoki.com/contents/files/89536063492.pdfIn PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/e458f8dbd79834644e35deff1093199e/88311644758.pdfIn PDF document text
    • http://form4concrete.ru/pics/cont/file/mejalolo.pdfIn PDF document text
    • https://mebelihome.ru/upload_picture/24696659068.pdfIn PDF document text
    • http://whkmradio.com/userfiles/file/27402784545.pdfIn PDF document text
    • http://copy-office.it/userfiles/file/vatud.pdfIn PDF document text
    • http://99hospitalitygroup.com/ckfinder/userfiles/files/10303066472.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614af1dc754ff---55139840069.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/8pk11qt99oo8p69b8bld5hbvk4/20023373790.pdfIn PDF document text
    • https://ivanda-commerce.hr/userfiles/file/46552952074.pdfIn PDF document text
    • http://wsospice.org/uploads/userfiles/file/file/78405490238.pdfIn PDF document text
    • http://azizavacanze.com/userfiles/files/kisopunowon.pdfIn PDF document text
    • http://studiolorenzino.eu/userfiles/files/zofavazike.pdfIn PDF document text
    • http://puzynowska-kancelaria.com/userfiles/file/44939769292.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/e365eb9c6524c2f5e56e82500aff02ad/rumowaz.pdfIn PDF document text
    • http://photou.cc/ckfinder/userfiles/files/sowifaluzemalogokafazafa.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_off0000c157.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC157 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d969.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD969 18560 bytes
SHA-256: 7f07e924c6352a4b0579ee435492c56527e2df28025e806ffa54c5c708ce4c4f
font_02_sfnt_off000109fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109FE 10656 bytes
SHA-256: 13af594cb919141128739a0a46796474dc7de0338a9712944528650b0b2930da