Malicious PDF — malware analysis report

Static analysis result for SHA-256 d09b16ab1823c4b5…

MALICIOUS

PDF

76.6 KB Created: 2021-09-03 00:01:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: c8c9f727d7aa090e4b3be043cac38049 SHA-1: c3d7c4c42a93dc4424f8d723eb02975346b13809 SHA-256: d09b16ab1823c4b58aee26eced1d05daf326048abcdb791e385958cca542f775
156 Risk Score

Malware Insights

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

The sample was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to various domains, many of which are hosted on compromised CMS upload storage or disposable hosting. The primary purpose appears to be directing users to external sites, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 http://jarosi.hu/files/file/41807325979.pdf In PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/cfe8d30986cee0aa7344eaabb5460584/86610243431.pdfIn PDF document text
    • https://toliveinchristjesus.ceosale.catholic.edu.au/application/third_party/ckfinder/userfiles/files/safumo.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/c0bda1784bbd6d9cde3dee70cd0cb276/63102956767.pdfIn PDF document text
    • http://yuhenganquan.com/userfiles/file/20210826085605_354252514.pdfIn PDF document text
    • https://goez1.com/10005001208290177/ckfinder/userfiles/files/86740504935.pdfIn PDF document text
    • https://abeess.com/userfiles/file/54338435394.pdfIn PDF document text
    • http://cedule-plachty.cz/files/file/43807350459.pdfIn PDF document text
    • http://beloezoloto.ru/userfiles/file/81413539420.pdfIn PDF document text
    • https://alteanetworks.fr/img/file/36694127300.pdfIn PDF document text
    • http://patroha.hu/file/5089389769.pdfIn PDF document text
    • http://www.ufolep-69.com/contenus/files/80172482013.pdfIn PDF document text
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/98789e48c3863a98aef7c808cd4d8ad1/30413834455.pdfIn PDF document text
    • https://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610bdd8a3e7fb---54605111399.pdfIn PDF document text
    • http://kleinschadenexpert.com/userfiles/file/53100399585.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/16123c40144a48---botukelavupozofix.pdfIn PDF document text
    • http://danies.ru/ckfinder/userfiles/files/69340584490.pdfIn PDF document text
    • https://adrfarysz.pl/userfiles/file/xozena.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087e0a6c3977---46034272698.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160a3c91e48518---ninez.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160717c68047ab---36232622410.pdfIn PDF document text
    • http://centroolosprato.it/userfiles/files/weriragaviv.pdfIn PDF document text
    • https://magnettoptan.com/upload/ckfinder/files/42634254291.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=pcl+xl+error+pdf+documentPDF 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_off0000c914.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC914 10564 bytes
SHA-256: 791b9e9fbfa6fa118ccb58a0f440010dce0d266c38e81d4b981f4e154cfecd99
font_01_sfnt_off0000e12f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE12F 16944 bytes
SHA-256: d51d3a9516941349471fa99da2192cc8aa007b29949686a63fb27a66768f4a4d
font_02_sfnt_off00010d0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D0B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1