Malicious PDF — malware analysis report

Static analysis result for SHA-256 84223676c8963fdf…

MALICIOUS

PDF

81.9 KB Created: 2021-09-11 03:08:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 54685cead193255bbb62c5d682176512 SHA-1: f6495f986068ea4e24ac87a1842d9b2784008d67 SHA-256: 84223676c8963fdff96685d1b60a0c17909b05b72b6861c6c7f379ea448f90ca
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm. The embedded JavaScript and numerous URLs, including those hosted on compromised CMS uploads, suggest an attempt to lure users to external sites. The primary purpose appears to be redirecting users through a series of links, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://krisoc.ru/uplcv?utm_term=etisalat+data+settings+android PDF link annotation
    • https://bykevin.com/wp-content/plugins/super-forms/uploads/php/files/649174da0d2a9bb89e4436223a8da231/44149539862.pdfIn PDF document text
    • https://noriupapildu.lt/ckfinder/userfiles/files/25743884303.pdfIn PDF document text
    • http://xn--80aaaaaikdebj9ccf1ayja1b5a3q.xn--p1ai/ckfinder/userfiles/files/lowefuximomoniwimol.pdfIn PDF document text
    • http://gimnazjum-krasiczyn.pl/img/userfiles/file/14426159780.pdfIn PDF document text
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139fee9c7a68---posaduvarex.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/ab063d42154991ea7e0f573a4656df73/22180794838.pdfIn PDF document text
    • http://kamienneogrody.com/userfiles/file/sezetifakugudijuwe.pdfIn PDF document text
    • https://network-italia.com/file/tederaximoxawaluzis.pdfIn PDF document text
    • http://orderleesushi.com/uploads/files/39077805668.pdfIn PDF document text
    • http://ettorebelfioreliutaio.it/userfiles/files/3575058015.pdfIn PDF document text
    • http://huseyindurmuslar.com/images_upload/files/24561953923.pdfIn PDF document text
    • http://friulanamarmi.it/images/file/logefopamologevubi.pdfIn PDF document text
    • http://kientrucphatloc.com/upload/files/begotogagos.pdfIn PDF document text
    • https://lazerom.pro/media/file/92439916484.pdfIn PDF document text
    • http://tkhomedeco.com/assets/uploads/ckedit/files/20210910174849.pdfIn PDF document text
    • http://elskenecologie.nl/files/18493815661.pdfIn PDF document text
    • http://sportsgarten.com/editorData/file/39168533886.pdfIn PDF document text
    • https://sgicorp.com/userfiles/files/wubitejevomilup.pdfIn PDF document text
    • https://weishinclinic.com/uploads/files/202109051250364928.pdfIn PDF document text
    • http://maezawa-jidousha.com/js/upload/files/51604611723.pdfIn PDF document text
    • https://defi128.phpascal.com/userfiles/files/zatuwijelumil.pdfIn PDF document text
    • http://muasamhangmy.com/ckfinder/userfiles/files/78305632751.pdfIn PDF document text
    • http://marcus-1.com/FileData/ckfinder/files/20210903_2222F1C7D99E0202.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/4mav0dso1fgfccblhtt0j8oau8/wajerotiju.pdfIn PDF document text
    • http://3qlohas.com/CKEdit/upload/files/kokomerevotalax.pdfIn PDF document text
    • 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_off0000dc8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC8C 17248 bytes
SHA-256: 8a9e1cace2cf6872c04f45dc4a3c955c039a72ec50c8698752dfaa3b68944673
font_01_sfnt_off000109e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109E2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000121f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121F9 10408 bytes
SHA-256: 2dab72dd0e3e671ad4e738cb758ee1f39489e45e7a89ea0f9420eb411631a4d1