Malicious PDF — malware analysis report

Static analysis result for SHA-256 98c13c1f21a2790d…

MALICIOUS

PDF

78.3 KB Created: 2021-08-27 08:52:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: c63d626a0437c5002e87dc33e36dd929 SHA-1: a553e252f749df992fd26401eef94d3a1032bbe8 SHA-256: 98c13c1f21a2790d4e30a1b5e9e16389bd38d05c876cb7e35a6377c5df7db13a
156 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it contains a link farm pointing to compromised WordPress upload storage and other disposable hosting, suggesting an attempt to redirect users to malicious sites. The document body is heavily obfuscated and unreadable, providing no direct clues to its intent beyond what the heuristics suggest.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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 https://www.nordatec.com/wp-content/plugins/super-forms/uploads/php/files/q9eofrerq0aghmoevpju7od79f/sunulazaw.pdf In PDF document text
    • https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/f7a72c4f46e251773e240366f46efe7b/mofezodobawu.pdfIn PDF document text
    • http://phongthuydotho.vn/upload/files/ravutekikejojosoloku.pdfIn PDF document text
    • http://sozopolihills.com/userfiles/file/54091715301.pdfIn PDF document text
    • https://olgapopovaphoto.com/wp-content/plugins/super-forms/uploads/php/files/b494872f212a7ad77cf652310f680740/rumonijimejuw.pdfIn PDF document text
    • http://stolocatering.ca/clients/874514/File/58036958885.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608843fcf1b7d---figesib.pdfIn PDF document text
    • https://artlabjo.com/userfiles/file/junuvu.pdfIn PDF document text
    • http://venturahigh1967.com/clients/40640/File/15796656306.pdfIn PDF document text
    • http://hongdacable.com/d/files/43291624681.pdfIn PDF document text
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/fe86d659c3746e018e6383a5b8ab0185/71574361387.pdfIn PDF document text
    • http://jerseybankruptcylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/55924178609.pdfIn PDF document text
    • https://securityguardsupply.org/php/uploads/file/1002804942.pdfIn PDF document text
    • https://burstallconrad.com/editor_files/file/suzasagegenipunun.pdfIn PDF document text
    • http://winkeleninzundert.nl/uploadimages/files/wemasolakujizel.pdfIn PDF document text
    • http://faizleathergloves.com/userfiles/files/tivupejitixisufoni.pdfIn PDF document text
    • https://www.nevjegykiraly.hu/userfiles/files/wisotusuwananiwaji.pdfIn PDF document text
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/smihp655r3l48pb8jqrmnnpq43/debub.pdfIn PDF document text
    • http://tuhs1970.com/clients/a/ac/acc339db084e87cdfae31a76a6c96f1c/File/66503088703.pdfIn PDF document text
    • https://vresponse.net/userfiles/file/wedipidexisu.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a49a3f2a091---7091329466.pdfIn PDF document text
    • https://rh-h1tapi-turbo.com/contents/files/63315888626.pdfIn PDF document text
    • https://abouelhoulgroup.com/userfiles/files/68008142788.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1609670c561bec---89743318195.pdfIn PDF document text
    • https://mmszke.hu/files/file/kubotedarebijati.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=the+quotient+of+20+and+a+numberPDF 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_off0000caad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAAD 17640 bytes
SHA-256: c33344f55775a89a6a90340f55159734915385f970978fb4e86c4844f6685b31
font_01_sfnt_off0000f9c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9C0 10996 bytes
SHA-256: 9df7cc960f965345f34bbbb8a41ba4515bf65b99a5c8021a55c2353a4808dde3
font_02_sfnt_off000112e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112E2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1