Malicious PDF — malware analysis report

Static analysis result for SHA-256 83c6db639dd5bb5b…

MALICIOUS

PDF

75.5 KB Created: 2021-09-17 10:12:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 491e5fa3a04669b822c8135d379053da SHA-1: 070da6726855f110c59df9cf504ad76d0f8e196e SHA-256: 83c6db639dd5bb5b2787da338848dcf5fef7681b4282d041ad1796d76c8af25d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The presence of a link farm pointing to various domains, some hosted on compromised CMS platforms, suggests an attempt to lure users to external sites. While no scripts were explicitly extracted, the nature of the link farm and the ML detection indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://orikon.net/Images_upload/files/11376798058.pdf In PDF document text
    • https://juniorclublivorno.com/sitonews/images_upload/files/85800646453.pdfIn PDF document text
    • http://arohitourandtravels.com/userfiles/file/kulavu.pdfIn PDF document text
    • http://konferencii.org/web/uploads/assets/file/zagunepevomanelurukisim.pdfIn PDF document text
    • https://propertiproperty.com/Uploads/userfiles/files/19650951291.pdfIn PDF document text
    • https://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/jsmhpftbc51skhb0l7gj1hrmo3/lomalu.pdfIn PDF document text
    • http://polyacer-ecp.com/userfiles/files/20210909_191550.pdfIn PDF document text
    • http://cuacongtudongbinhduong.com/upload/files/sejarunupopuxikulapi.pdfIn PDF document text
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/7644e6100b272a1cac713714c773c2ae/73651186622.pdfIn PDF document text
    • http://gddfboiler.com/uploads/files/99719300826.pdfIn PDF document text
    • https://www.tunnel.de/files/uploaded/file/joloxuk.pdfIn PDF document text
    • http://dangkydoanhnghiep.org/hinhanh_fckeditor/file/79383671650.pdfIn PDF document text
    • https://butyfarm.mm520.net/userfiles/files/tanujowesirutebiwax.pdfIn PDF document text
    • http://designerhouse.ru/upload/files/baniga.pdfIn PDF document text
    • https://eric-parnes.shortex.com/ckfinder/userfiles/files/58064524646.pdfIn PDF document text
    • https://canionglobal.com/FCKeditor/file/dixiputefagaxumefu.pdfIn PDF document text
    • https://riwg.in/userfiles/file/pomozizopok.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16141b3141556a---35062460785.pdfIn PDF document text
    • http://headlinesdinerla.com/uploads/files/53854112980.pdfIn PDF document text
    • https://instalacje-elektryczne.net/ckfinder/userfiles/files/24310148793.pdfIn PDF document text
    • http://cravaluos.com/ckfinder/userfiles/files/jesomirafujenifazototifew.pdfIn PDF document text
    • https://vaitinhdien.com/app/webroot/upload/files/41151356832.pdfIn PDF document text
    • http://gs-metals.com/filespath/files/20210903132649.pdfIn PDF document text
    • https://maintogelonline2.bet/contents/files/jefipuxiwunofogosu.pdfIn PDF document text
    • http://perksys.com/userfiles/file/bodetolafiwuref.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=mini+block+craft+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_off0000bfbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFBF 10624 bytes
SHA-256: 9d4b4b068ad799beb2e446c165bb4daa271e3ea1c565e3b6232ae34f13b4f7ab
font_01_sfnt_off0000d7fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7FC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f00e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF00E 18648 bytes
SHA-256: 3c52ecb01175f00c370477e25862193558856ee0dc21ab5b2b58682a2e47918b