Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3bba9df1f4a3099…

MALICIOUS

PDF

81.6 KB Created: 2021-09-22 09:25:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 31f85c34fd7f7630c9be2b865dc67327 SHA-1: d9a03a3337d8b66d2a3968700129b3af51dd6a16 SHA-256: a3bba9df1f4a3099c5477505907a014d4713e66786f08e1dabb7d782b34c0db1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged by multiple heuristics as a link farm, with many URLs pointing to compromised or disposable hosting. The ML classifier and ClamAV also identified it as malicious, specifically a phishing trojan. While no scripts were extracted, the structure and URL patterns suggest an attempt to direct users to download further content, likely for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://rent-lease-no1.com/userfiles/file/20210910060508.pdf In PDF document text
    • http://easyhypermarket.com/userfiles/file/fefobarapo.pdfIn PDF document text
    • https://magnettoptan.com/upload/ckfinder/files/43559090784.pdfIn PDF document text
    • http://mu-rrrc.com/userfiles/file/wikavov.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140fce862cc2---nobedoxabepajepale.pdfIn PDF document text
    • https://lionkingbali.com/uploads/file/5107045273.pdfIn PDF document text
    • http://na-bytecek.cz/UserFiles/File/legajolalopowunawuwu.pdfIn PDF document text
    • https://casalindasbakery.com/ckfinder/userfiles/files/wumasovopilij.pdfIn PDF document text
    • https://mariellatriolo.it/public/file/81024400435.pdfIn PDF document text
    • http://sweet-sugar.de/images/uploadedimages/file/lanekoku.pdfIn PDF document text
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f1c430e084---2576914299.pdfIn PDF document text
    • http://tuanayapim.com/rsm/files/wemijetipinuvu.pdfIn PDF document text
    • http://www.tractortools.cz/ckfinder/userfiles/files/54632314033.pdfIn PDF document text
    • https://dzido.pl/userfiles/file/gutaribo.pdfIn PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16142bbe279c9b---sedefumomojuxuxef.pdfIn PDF document text
    • http://locnuocvietmy.com/Images_upload/files/78972663978.pdfIn PDF document text
    • https://mytutr.com/wp-content/plugins/super-forms/uploads/php/files/acb1bbec2a781a95e25da7af975879c8/guxebimixabunof.pdfIn PDF document text
    • http://liavanhaeringen.nl/userfiles/files/kexipema.pdfIn PDF document text
    • http://jarauwerdaenzn.nl/userfiles/file/44237842528.pdfIn PDF document text
    • https://mami-m.com/Uploads/userfiles/files/85982733251.pdfIn PDF document text
    • http://theaterbuehne-schwandorf.de/userfiles/file/7551688932.pdfIn PDF document text
    • http://automsystem.com/UploadFile/file/20210919014506336.pdfIn PDF document text
    • http://automotiveenergy.cz/userfiles/file/votobiwuziwudorovemotar.pdfIn PDF document text
    • http://forma8.kz/ckfinder/userfiles/files/zuzekimipomidomi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=preset+download+apkPDF 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_off0000d98d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD98D 10472 bytes
SHA-256: bbdb7f5bf955290cda677a9fee50bb3faf331671129bb0cf76028061b4e1ce32
font_01_sfnt_off0000f197.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF197 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000109a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109A9 18336 bytes
SHA-256: 97f7b995687fd6531710b7dd0d33676bb4f618283691c0404565db6dc12b5dd6