Malicious PDF — malware analysis report

Static analysis result for SHA-256 75c66d1580f47912…

MALICIOUS

PDF

80.4 KB Created: 2021-09-06 09:28:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f431358e920b04280c1e71def8215b34 SHA-1: 932fbd530fa24ea398cc78a404192a960f81d101 SHA-256: 75c66d1580f47912f3b350181c3d461944eddd7511d0570b011f507591cfa756
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with multiple URLs pointing to compromised WordPress upload storage, suggesting an attempt to host and distribute a secondary payload. The presence of embedded URLs and the 'Download Button' heuristic further support this, indicating a lure to download malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f9278a85a02---gubazikexekepupetarera.pdf In PDF document text
    • https://arhometutor.com/userfiles/file/mabusi.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/faaf95130008b9fba75b5de94d4f8c92/72615500162.pdfIn PDF document text
    • http://forumcutuca.com/ckfinder/userfiles/files/wisasagexeso.pdfIn PDF document text
    • https://propiedades.net/ckfinder/userfiles/files/60775664606.pdfIn PDF document text
    • https://apparel.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/808ffd363e7eb3d5f13ce75da1d97f23/denaxisuvawiririnug.pdfIn PDF document text
    • http://suamayin.biz/userfiles/file/ditumowemefifowig.pdfIn PDF document text
    • https://clubkdo.fr/img/pics/files/46942265003.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c4865c758b5---gusemudoju.pdfIn PDF document text
    • http://ardechetendancebrut.fr/userfiles/ardechetendancebrut.fr/file/97172775597.pdfIn PDF document text
    • http://generale-bureautique.fr/gdb/files/file/jusidafopadofexemiginopij.pdfIn PDF document text
    • http://bahattinburyan.com/userfiles/file/99741205630.pdfIn PDF document text
    • http://ysenb.kr/board/file/editor/file/66035587190.pdfIn PDF document text
    • http://www.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/8f465fbed08def367c7569316b1bcd54/13442144296.pdfIn PDF document text
    • http://asea-admin.com/_userfiles/file/20210629021116.pdfIn PDF document text
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/4ccuim1s4ffu3r9t3201ocigmr/77340552463.pdfIn PDF document text
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132e0d7000db---xoxonanafisokarerolamovam.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/cb983a52ff561040448e791b9164f54e/fowetulazerujisajakusu.pdfIn PDF document text
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/e57879d02aa2afa3dd40e55dd0702a21/62466457423.pdfIn PDF document text
    • http://astorandblack.net/emailer/userfiles/file/32722806495.pdfIn PDF document text
    • https://bloomeng.com/uploads/lukamemusurezujiroda.pdfIn PDF document text
    • http://bkdesign.ee/userfiles/file/wurojew.pdfIn PDF document text
    • http://luckdidea.com/ckfinder/images_store/files/88675378579.pdfIn PDF document text
    • https://ecowaytechnologies.com/ckfinder/userfiles/files/14307364149.pdfIn PDF document text
    • https://justforjetscatering.com/userfiles/image/files/nizewenifariket.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=principles+of+engineering+thermodynamics+8th+edition+solution+pdfPDF 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_off0000d283.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD283 11492 bytes
SHA-256: de514a10e63529b04fcecc849ea441b182bc63ecb1bc81afe428103f9a0c2462
font_01_sfnt_off0000ed54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED54 17428 bytes
SHA-256: 647d9ce67fc2d266d28e02ad6f2b9723fcea87d0dfbe85b641e5e4e9265460df
font_02_sfnt_off00011afc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AFC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1