Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8395cac2da01e87…

MALICIOUS

PDF

73.3 KB Created: 2021-09-30 21:08:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: d4f7817f998370e3c2d38da3d15c2a80 SHA-1: e1151c9f51faee50c06eac25f93f99051e4f27a0 SHA-256: b8395cac2da01e87a827fbd92a7aede3fa9660f3e51bc729645995d268a79f96
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be associated with compromised content management systems or disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of a link farm on potentially untrusted domains suggests an attempt to lure users to malicious content.

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://crewmak.ru/uplcv?utm_term=sherlock+holmes+the+norwood+mystery+answers PDF link annotation
    • http://zhongyuemedia.com/filespath/files/20210929165901.pdfIn PDF document text
    • https://studioconcept-stand.com/fck_userfiles/file/supowem.pdfIn PDF document text
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613d890089567---88092183881.pdfIn PDF document text
    • https://gikguamerica.com/userfiles/file/57616016060.pdfIn PDF document text
    • http://www.loicadesacavem.pt/wp-content/plugins/formcraft/file-upload/server/content/files/16148749aa9dc6---wimomutis.pdfIn PDF document text
    • https://www.ciabrini-immobilier.com/wp-content/plugins/super-forms/uploads/php/files/1rjh5vtsfk3gtenivfdcau6o5j/9084766750.pdfIn PDF document text
    • https://jager-ig.tw/up_photo/file/kefiwosojamalepirifop.pdfIn PDF document text
    • http://brmxn.com/userfiles/file/20210918045148_j3np5u.pdfIn PDF document text
    • http://yey.uw52.com/upload/files/64564400940.pdfIn PDF document text
    • http://bortran.com/upload/image/file/20210906023353.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/06ad999631f393a1dd60f39b3583ae28/57070686423.pdfIn PDF document text
    • https://muratay.nl/userfiles/file/72283676340.pdfIn PDF document text
    • https://playworkspartnership.ca/sites/default/files/file/siziwobixu.pdfIn PDF document text
    • https://fotokeramika.bg/userfiles/file/46170142513.pdfIn PDF document text
    • http://fantasymusic.it/userfiles/files/48649115902.pdfIn PDF document text
    • http://odra.cycling-recycling.eu/imgturysta/files/sedimej.pdfIn PDF document text
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/4c45e7de8a9421af40edd87fa9b18c23/57498143413.pdfIn PDF document text
    • http://studioagronomoserragiotto.eu/userfiles/files/55190762923.pdfIn PDF document text
    • http://hcstonetw.com/uploads/files/202109211202088142.pdfIn PDF document text
    • http://bestapp4u.com/admin/uploadedfiles/file/60330778454.pdfIn PDF document text
    • http://clinicaveterinariamontecchia.com/userfiles/files/zakolisojikokupatakegow.pdfIn PDF document text
    • http://akinmedikal.com/uploads/file/42716126744.pdfIn PDF document text
    • https://i-intelli.com/ckfinder/userfiles/files/ruteb.pdfIn PDF document text
    • https://hanyauntuktesting.com/contents/files/91522530544.pdfIn PDF document text
    • http://win-sonic.com/ck_imgs/files/46890611753.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_off0000b662.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB662 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ce74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE74 17716 bytes
SHA-256: da86276f64632ec7e3457ab18af51d2a8e005c3982cbd1b023cabebee45d4c7e
font_02_sfnt_off0000fc03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC03 10912 bytes
SHA-256: 761fc136b59ae10e3ff62b3cc348fbcc7ae87325557cd422fe1b0493607746cb