Malicious PDF — malware analysis report

Static analysis result for SHA-256 87cfb9807ca06b69…

MALICIOUS

PDF

90.5 KB Created: 2021-09-13 09:43:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 5b47d1421365dd732cdafc76e12d4662 SHA-1: f6b696d502487e578ce5c97e13c09ccf2b326d6c SHA-256: 87cfb9807ca06b69ece566715d9050b5d2f8fd029bd709959a18b53c61630697
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

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://icmasistemas.com/userfiles/files/fawimuzizox.pdf In PDF document text
    • https://purevdavaa.mn/uploads/ckfinder/files/lizomipirafebamufepiv.pdfIn PDF document text
    • https://maintogelonline.info/contents/files/31798819966.pdfIn PDF document text
    • http://yejida.com/userfiles/file/57841385470.pdfIn PDF document text
    • http://tahyuh.com/uploads/files/202109121322117895.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16135ba9c2b94b---53650410288.pdfIn PDF document text
    • http://secondhandgraphics.com/usrfiles/file/69653024147.pdfIn PDF document text
    • http://ordineveterinarivenezia.eu/userfiles/files/nataziveravepunej.pdfIn PDF document text
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/d745424b88fbd49e64f495b2f2147e33/saxegufivibebalegejinu.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613d5bd9abe52---gogadepazaveru.pdfIn PDF document text
    • https://bizimpin.com/calisma2/files/uploads/65665332995.pdfIn PDF document text
    • http://ooexperience.be/assets/Image/files/nesezufitu.pdfIn PDF document text
    • http://ebus.cn/up_file/file/lapagakurigaveriz.pdfIn PDF document text
    • http://tc-muehlacker.de/data/tcmuehlacker/userfiles/file/xutirebekugowujuboti.pdfIn PDF document text
    • http://princeworldwide.com/multimedia/userfiles/file/xoxarewunazaluropaxalol.pdfIn PDF document text
    • http://grandioso.asia/editor_upload_image/file/siliburazofisugafu.pdfIn PDF document text
    • https://tadimtursu.com/image/files/43430191648.pdfIn PDF document text
    • http://vanillasky-ch.com/images/files/romarajamirokaxa.pdfIn PDF document text
    • http://chiari-web.com/ckfinder/optimist/files/tenogekinimu.pdfIn PDF document text
    • http://toanthinh.vn/webroot/img/files/93437512489.pdfIn PDF document text
    • https://groupunsur3.com/contents/files/21627521214.pdfIn PDF document text
    • https://onutglen.com/caningest/images/file/15505625289.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613ae554d7797---guvanonu.pdfIn PDF document text
    • https://aristi-trap.com/upload/users/files/89095481646.pdfIn PDF document text
    • http://nedvizhimost-v-sharm-el-sheikhe.ru/uploads/files/53340912541.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=how+to+download+hbo+max+app+on+firestickPDF 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_off0000f79c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF79C 11296 bytes
SHA-256: af9e5202e57bac5010e059e2c64d1f25b5f63afa3176f8fb6e58a2292a66dadd
font_01_sfnt_off000111b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111B6 19120 bytes
SHA-256: fd50f869751e615cc9e660a041f47068f84c212cc4ca4570ff967ed585878920
font_02_sfnt_off0001438b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1438B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1