Malicious PDF — malware analysis report

Static analysis result for SHA-256 275c4e6022da8e73…

MALICIOUS

PDF

85.4 KB Created: 2021-09-17 22:47:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e936bf0861caac9680c217d19b29660c SHA-1: 5c17e459f4e08cdf16f8924924d23949613ee08f SHA-256: 275c4e6022da8e73b2ad481bb67abcda50d71c2dafc850e5b42b9c16f3e5e8a6
172 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and ML classifiers. It contains embedded JavaScript and multiple external links, some pointing to compromised WordPress sites, suggesting an attempt to redirect users to malicious content or download further payloads. The presence of a 'download button' heuristic further supports a social engineering lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 8

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://sualpturizm.com/userfiles/file/gimida.pdf
    • http://mnogonomerov.ru/uploads/file/93122928175.pdf
    • http://targhevaticane.it/userfiles/files/74691767167.pdf
    • http://jjmcp.jp/userfiles/Image/file/misokojixewevozitikazos.pdf
    • http://ekonopuntos.com/campannas/file/90852158253.pdf
    • https://xn--fiqa735be48e.com/upload/files/21411485949.pdf
    • https://mobisteelegypt.net/userfiles/file/94227561066.pdf
    • https://hkpefa.org/editor_upload/file/98405956919.pdf
    • http://suncitygroup.ir/basefile/suncitygroupir/files/85618597105.pdf
    • http://haokunchem.cn/upload/files/70082382544.pdf
    • https://matricula.netlandschool.cl/files/tenalotuk.pdf
    • http://xn--80aap0abfiql8h.xn--p1ai/admin/ckfinder/userfiles/files/jewixew.pdf
    • http://centroolosprato.it/userfiles/files/26898222965.pdf
    • https://altaitur.com/ckfinder/userfiles/files/46399700185.pdf
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/161413e96aee83---mirizivar.pdf
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/h2j0kl4jdlctthk3u27mbq430a/delotetumobemetoz.pdf
    • http://werder-ritter.de/UserFiles/File/36334706503.pdf
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/641bfd182a86efe8811ddbbd019f2088/4204241208.pdf
    • http://vodnik48.ru/content/file/9552729077.pdf
    • http://ouhkpthaa.org/userfiles/sopagefaremod.pdf
    • http://smolninskayahotel.com/userfiles/file/zutafiven.pdf
    • http://due.pt/js/ckfinder/userfiles/files/81114594120.pdf
    • http://villkasz.hu/editor_up/3258243276.pdf
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1613a307d6156f---texab.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=utorrent+pro+apk+free
    • 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_off0000e469.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE469 16792 bytes
font_01_sfnt_off0000fc80.bin
a2cb830b258abd1db2c1696398e4750e09c78d301a5c3dbccad91b8763ceb571
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC80 10144 bytes
font_02_sfnt_off00011349.bin
005cc760fceccc414a415631478541d4ee9293cbb45755631a58d138d25fa7bf
pdf-font-stream PDF embedded font (sfnt) at offset 0x11349 19992 bytes