Malicious PDF — malware analysis report

Static analysis result for SHA-256 81f998241a98941c…

MALICIOUS

PDF

83.2 KB Created: 2021-09-21 07:33:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6b215cda0348569c93fb4746a95e19e8 SHA-1: 9f10873f469d3de46bd4a5a1428baa694eb4fd54 SHA-256: 81f998241a98941cb3f3892df46342b6a400178b39b687e7717283cdc7ba4baf
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it is a link farm and a callback phishing lure. Although no scripts were directly extracted, the PDF structure and embedded URLs suggest an attempt to redirect the user to malicious content or solicit a callback for fraudulent purposes. The presence of multiple links, some pointing to potentially disposable hosting, reinforces the phishing and redirection intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161442519593ef---bolavokavujag.pdf In PDF document text
    • https://vgi-vn.vn/app/webroot/img/files/5342249245.pdfIn PDF document text
    • http://litho-and-co.fr/ckeditor/upload/files/51017858682.pdfIn PDF document text
    • http://zechnerbau.at/images/content/files/vogekenepidomavozolowaz.pdfIn PDF document text
    • http://www.synagoge-stommeln.de/ckfinder/userfiles/files/63426874167.pdfIn PDF document text
    • http://104.156.58.56/~web2inbox/wp-content/plugins/formcraft/file-upload/server/content/files/1613ac7e336c16---48409591474.pdfPDF link annotation
    • http://unibeauty.com.br/ckfinder/userfiles/files/doniwag.pdfIn PDF document text
    • https://apoiotelecom.com/imagens/img_fckeditor/file/wuliwefujezinomidoz.pdfIn PDF document text
    • http://miroslaws.com/ckfinder/userfiles/files/gegotinugagomemikixefas.pdfIn PDF document text
    • https://www.xyoaa.org/sites/default/files/files/gegidopigi.pdfIn PDF document text
    • http://cnkls.com/userfiles/file/1631615889.pdfIn PDF document text
    • http://zamdq.com/filespath/files/20210913172013.pdfIn PDF document text
    • http://tokyosushilohaus.com/uploads/files/77094027469.pdfIn PDF document text
    • http://kenzoum.org/home/integrity/public_html/ckfinder/userfiles/files/fenuweka.pdfIn PDF document text
    • https://onderdurdu.com/upload/ckfinder/files/funeluwijilineb.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161467d1e1e959---82391636147.pdfIn PDF document text
    • http://axi-hohenstein.de/userfiles/file/gonipidifib.pdfIn PDF document text
    • https://belitour.ir/basefile/belitourir/files/81838679629.pdfIn PDF document text
    • http://bluekeydigital.com/images/pic/file/pamiweg.pdfIn PDF document text
    • http://marisqueandopremios.com/campannas/file/704714931.pdfIn PDF document text
    • https://beysukonaklari.com/ckfinder/userfiles/files/wuzilidegosatapabexuxunu.pdfIn PDF document text
    • http://www.patriarca-batiment.com/ressource/site-image/files/bamafuderebejanusexili.pdfIn PDF document text
    • https://avflash.nl/upload/files/9517289791.pdfIn PDF document text
    • http://futureinfashion.com/ckfinder/userfiles/files/45198489198.pdfIn PDF document text
    • https://techson-cctv.com/upload/file/11770880387.pdfIn PDF document text
    • http://guerrazzi.info/userfiles/files/53349299145.pdfIn PDF document text
    • http://susasoft.com/upload/userfiles/files/vukotexoniwupopalexiva.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=idle+heroes+generator+no+verificationPDF 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_off0000de79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE79 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f68b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF68B 18260 bytes
SHA-256: 451f3fd3edc1829b85e5b7872e9503e63b7d436f79da3e93cb0da612b52cc202
font_02_sfnt_off000125d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125D8 10772 bytes
SHA-256: a80d15ae9247d8009ceeb54f98d2ca2ec95b38a6fb5522c6c2b66f64de107e92