Malicious PDF — malware analysis report

Static analysis result for SHA-256 d577ee4d107af5a0…

MALICIOUS

PDF

77.0 KB Created: 2021-08-03 07:48:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5cf5c01e5eb86ce0a5e35cec871775d8 SHA-1: 5293bbe2f08cab03821fa270200cb0d6be8dc43b SHA-256: d577ee4d107af5a02382a6f77e83d5d11ed9e7a07616fada3bddbf57b0bfd789
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links to external websites, many hosted on compromised CMS platforms or disposable domains, suggesting a phishing or malware distribution scheme. The document body is heavily obfuscated and appears to be non-readable content, further indicating a malicious intent rather than legitimate document sharing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://mashura.co/userfiles/files/1064175128.pdf
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bf84fc3b33a---46524530152.pdf
    • http://asude.istanbul/ck_images/files/89896606055.pdf
    • http://blankheich.de/images/uploads/file/21099928494.pdf
    • http://webscape.co.bw/wp-content/plugins/formcraft/file-upload/server/content/files/1607dd9c12a01a---79006834902.pdf
    • https://expresstestingatl.com/wp-content/plugins/super-forms/uploads/php/files/7dc25fe704d586fb1ed7b95cbca134bf/sakarajofon.pdf
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/344fce2249807bd5be322743d85f4e06/10924010101.pdf
    • https://autotrans911.com/thread/admin/uploads/file/39763884867.pdf
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/8ed99559e95362f00ba0ae2f7c83debb/pakalajuxe.pdf
    • https://www.nestroots.com/wp-content/plugins/super-forms/uploads/php/files/lsestcu2pass6l3nqs220iusc3/tulixugoduguwi.pdf
    • http://conomiya.com/images/uploadedimages/file/52589903011.pdf
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/1708a0133316dc01ac5fa0df555e4c99/61990027194.pdf
    • https://baxsporthorses.nl/userfiles/file/kogezelebulo.pdf
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607c61f35a16d---46800428087.pdf
    • http://grapevinewinerytrail.com/clients/876125/File/dixitixotutekuxel.pdf
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/160f30fcfdf9ab---renipokugotikibenis.pdf
    • http://mesamiesdallas.org/clients/e/ee/ee8f1390623de39be1ac2b47a321719d/File/piwinurusiwimekemakene.pdf
    • http://evansmedia.ca/userfiles/file/fewidajumilu.pdf
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/b8d4e2f38c6e67846edce54857fc3c63/33149484821.pdf
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d9ce590038---42633967962.pdf
    • http://www.dj-csnl.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a1a990b1c4f---70072692643.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=will+exercise+help+spondylolisthesis
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cc4a.bin
f5788d255d05ab4533045870943d7107181efdada7704ba1feb752c38e4bc9ed
pdf-font-stream PDF embedded font (sfnt) at offset 0xCC4A 15776 bytes
font_01_sfnt_off0000f4a9.bin
6b23c76735c13ab9a298371dfa3bcf17afb70ed00ae2bb8c26d3aca4127c293a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4A9 10656 bytes
font_02_sfnt_off00010d0a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D0A 16792 bytes