Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b71a89e7b5bc1c5…

MALICIOUS

PDF

72.9 KB Created: 2021-09-17 01:50:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 1145a25b0c736ea2426a8ce6898148eb SHA-1: 93adee3d4494c2e5836af8ad5cd61811cf99d31f SHA-256: 6b71a89e7b5bc1c5404534b42c725378d918a8d165223979bb51c71c1ca2eb8b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous embedded URLs pointing to compromised or disposable domains, indicative of a link farm designed to redirect users to malicious sites. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware delivery. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' confirms the nature of the document as a collection of links on potentially untrustworthy hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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 https://wastran.ru/uplcv?utm_term=how+to+remove+app+name+from+toolbar+in+android PDF link annotation
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/45bebd9e7d5f3559d3da36d2f0f6d80f/81037912438.pdfIn PDF document text
    • https://wrd13.com/force/file/gititig.pdfIn PDF document text
    • http://abwninemile.com/uploads/files/welosujenopivovaxumi.pdfIn PDF document text
    • https://businessincasey.com.au/application/third_party/ckfinder/userfiles/files/20052422052.pdfIn PDF document text
    • http://studiocinti.eu/userfiles/files/16124488648.pdfIn PDF document text
    • https://atlas-consulting.ro/fckeditor/fisiere/file/zegamubogarapi.pdfIn PDF document text
    • https://www.assofmt.org/ckfinder/userfiles/files/wisor.pdfIn PDF document text
    • http://nocleginaplus.pl/uploads/userfiles/files/91934499956.pdfIn PDF document text
    • http://stellarp.com/userfiles/files/kokibirodonixitugemigugor.pdfIn PDF document text
    • http://vietkinggroup.com/uploads/userfiles/file/durodedufevuzomuvonos.pdfIn PDF document text
    • http://www.travelwithtaangoo.com/img/file/74405324278.pdfIn PDF document text
    • http://barcelonasixtytwo.com/userfiles/file/44451066089.pdfIn PDF document text
    • http://www.mostenpo.jp/userfiles/files/jiwixopaposoginedo.pdfIn PDF document text
    • http://studioriboldi.eu/userfiles/files/toxasabakekupirujaraxuf.pdfIn PDF document text
    • http://www.aceitunasdelguadalhorce.es/ckfinder/userfiles/files/78773137497.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f87e38e972---66597117.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613068865d461---zavivokirawireruli.pdfIn PDF document text
    • http://aan.kz/ckfinder/userfiles/files/wobukonosoxiwivowilo.pdfIn PDF document text
    • http://liburnia.pl/userfiles/file/majigeluwenadekiferan.pdfIn PDF document text
    • http://www.morrisjones.co.uk/EditorImages/file/959371929.pdfIn PDF document text
    • http://k-sta.kr/FileData/ckfinder/files/20210914_762D36AB76CC77C0.pdfIn PDF document text
    • http://bluebirdcanada.com/FileData/ckfinder/files/20210908_79C4F06F8A25CEE2.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_off0000babe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBABE 10776 bytes
SHA-256: 0b602523bb053f7a7318cba7aad9303e0058382f4cd8c898817cf2eb7a60d477
font_01_sfnt_off0000d342.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD342 16500 bytes
SHA-256: a54910997e9c14d44ef6b796f419fd77e5918eecaf8f748b4cbe09ddc0e7d274
font_02_sfnt_off0000fdcc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDCC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1