Malicious PDF — malware analysis report

Static analysis result for SHA-256 e501591d5244ff7f…

MALICIOUS

PDF

70.2 KB Created: 2021-10-03 04:11:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6218068f5197aab1b35da92f535d8dbb SHA-1: 1d6b008db163c7662b7f6de0ee22e5879eb7926d SHA-256: e501591d5244ff7f4837e7def7ccc61d3b234344a3e69ffebaab3270e65db9e0
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, and it contains embedded JavaScript. The PDF also hosts a link farm pointing to various external PDF files, some of which are hosted on compromised WordPress sites, suggesting an attempt to redirect users to malicious content. The presence of JavaScript and the link farm indicate a multi-stage attack, likely involving phishing or the distribution of further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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.
  • 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.
  • 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://medicom.pl/userfiles/file/poxewebuzatazipowas.pdf
    • https://palezieux.com/ckfinder/userfiles/files/xusefadiximisotofenepelux.pdf
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16134f8a8e7cb9---63908076079.pdf
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/8cedf971504e93f0b3d566f45f5ea1b9/gaboxisodozukotaxodibefo.pdf
    • http://whatifitspossible.com/ckfinder/userfiles/files/53949321627.pdf
    • http://oris-am.com/editor_up/visuzigitaxenigob.pdf
    • http://denkobarbell.com/_upload/files/87718261646.pdf
    • http://www.deco-interieure.com/userfiles/file/45508234605.pdf
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/161538eb846aa4---87629903338.pdf
    • http://aaaa.handyfriendship.com/upload/files/46659480030.pdf
    • https://hotnews.md/upload/userfiles/files/93920261579.pdf
    • https://takarasushimn.com/userfiles/files/19135112663.pdf
    • http://hmconcretemixingplant.ru/d/files/69503901352.pdf
    • http://barudan.hk/UploadFile/file/20210915153449313.pdf
    • http://www.tiande-global.com/ckfinder/userfiles/files/guvemavatirom.pdf
    • https://landbar.com/app/webroot/js/ckfinder/core/connector/upload/files/panesowira.pdf
    • https://togelunited4d.com/contents/files/97853269974.pdf
    • http://girisimcilikproje.com/resimler/files/48077616268.pdf
    • http://progfin.pl/userfiles/file/jazafeximowixozijufoto.pdf
    • https://vuaship.com/wp-content/plugins/super-forms/uploads/php/files/8vm5kccnfk34533cavj4vtvcu2/duvig.pdf
    • https://lasanisports.com/files/noxitoxorirenujav.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=10+causes+for+childhood+obesity
    • 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_off0000af69.bin
390db6c9c8947173826a8cf5f0f24e824baf1c0e0dc66c9dd2953e53604fe499
pdf-font-stream PDF embedded font (sfnt) at offset 0xAF69 10900 bytes
font_01_sfnt_off0000c8c6.bin
41f22a9c381c2af4945cb5fc1de69228f83023619d027a26018da203bc146417
pdf-font-stream PDF embedded font (sfnt) at offset 0xC8C6 16764 bytes
font_02_sfnt_off0000f3b0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF3B0 16792 bytes