Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9b20778514f67d6…

MALICIOUS

PDF

81.3 KB Created: 2021-09-08 21:43:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 6d194e8467514b65c3c4ef083bb1b8bf SHA-1: 6c6c78aa049c7e413ef1795f9aa1111889c419f8 SHA-256: b9b20778514f67d65770850c50593d1f56ca543d68aaa7da638a653bb1956522
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified the document as a link farm, with many URLs pointing to disposable hosting or compromised WordPress sites. The presence of embedded URLs and the nature of the heuristics suggest an attempt to direct users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://krisoc.ru/uplcv?utm_term=configurer+compte+aliceadsl+sur+android PDF link annotation
    • http://altiro.nl/home/tjerk/file/gevures.pdfIn PDF document text
    • https://archcosmeticstudio.com.au/wp-content/plugins/super-forms/uploads/php/files/4056f92e595d96a880d68e70f8b2b81f/58997444665.pdfIn PDF document text
    • http://doudou.tw/userfiles/files/71823712804.pdfIn PDF document text
    • http://wonderpanel.com/app/webroot/img/file/soliwoduxezasika.pdfIn PDF document text
    • https://acavacecio.it/userfiles/files/laruxekudibaxasokewili.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/c707a4c10446fd8c3bbd85956c2cd2a4/38878671169.pdfIn PDF document text
    • http://elandtour.com/FileData/ckfinder/files/20210905_A01A58EFDCC32F5F.pdfIn PDF document text
    • http://apvn.info/userfiles/file/43539641136.pdfIn PDF document text
    • http://zensushialiso.com/uploads/files/78495884903.pdfIn PDF document text
    • http://28777886.com/Lpf/UPFILE/userfiles/files/tozutowisakikenum.pdfIn PDF document text
    • http://china-zub.ru/userfiles/file/gizozakofazorimijinod.pdfIn PDF document text
    • https://jjcfurnituremaker.com/userfiles/files/3859349285.pdfIn PDF document text
    • http://sarljarry.com/userfiles/file/40521486079.pdfIn PDF document text
    • http://stickerbarcode.com/file_media/file_image/file/gativuta.pdfIn PDF document text
    • https://printsolutions.printsolutions.bg/uploads/wysiwyg/files/rilig.pdfIn PDF document text
    • http://wsmr.us/userfiles/file/75258785080.pdfIn PDF document text
    • http://marathon-gexin.com/Uploadfiles/files/60749653394.pdfIn PDF document text
    • http://busto-wl.gattinonimondodivacanze.it/themes/userfiles/files/badibimezobeboparomeniwu.pdfIn PDF document text
    • http://stressmanagement-karriere.de/userfiles/file/1180506182.pdfIn PDF document text
    • http://limeitec.com/upfiles/editor/files/gamugugunevogoruka.pdfIn PDF document text
    • https://shreenatharcade.com/userfiles/file/loxaxedalefugijomanawexub.pdfIn PDF document text
    • http://totoumi.jp/upload/file/29486185447.pdfIn PDF document text
    • http://diplomat2014.ru/ckfinder/userfiles/files/letukaxobaradak.pdfIn PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/0036248a381c3fff67cac62d535e3300/28839829149.pdfIn PDF document text
    • http://wintec-samu.hu/uploads/files/50642498747.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_off0000d48e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD48E 19652 bytes
SHA-256: b2a528c571635996e5ce1710eed29c4972bc603e54c83b63f6bc902e7096892d
font_01_sfnt_off000105bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105BD 11092 bytes
SHA-256: 10b63fa944e275bcf8c52714b8c681a950a158fd096ee02bd4a1a444b2e05a39
font_02_sfnt_off00011f70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F70 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1