Malicious PDF — malware analysis report

Static analysis result for SHA-256 de256898545b0432…

MALICIOUS

PDF

85.1 KB Created: 2021-09-18 09:49:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 3a218281b63bb0911cba7fd22bdd34a5 SHA-1: 040a6da09d4bdd28cd0a68d055aef18942bc3f40 SHA-256: de256898545b0432073a0a018b6ddecf04def6d81b0040b45c7770a743ac0d18
164 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous external links, many pointing to compromised CMS uploads or disposable hosting, indicating a malicious intent to redirect users. The ML classifier and ClamAV detection strongly support this assessment, classifying the file as a phishing trojan. The embedded JavaScript likely facilitates the redirection or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • 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://synerhu.ru/uplcv?utm_term=nba+2k+locker+codes+today PDF link annotation
    • https://gregoryshow.ru/files/file/90218649398.pdfIn PDF document text
    • http://change4best.ru/upload/file/muzanepakasejopaperedu.pdfIn PDF document text
    • http://sochi-riba.ru/ckfinder/userfiles/files/dilodudidevimagerel.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613c8f8993198---kosiziwa.pdfIn PDF document text
    • http://moscow-vernisage.com/files/files/10909035915.pdfIn PDF document text
    • https://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/d2vntgm3hnd2tbpbee4caev1b6/guvotaz.pdfIn PDF document text
    • http://phuketdriveschool.com/userfiles/file/pogavopuraxosadevaro.pdfIn PDF document text
    • http://graciaindoutama.com/kingkong/userfiles/files/51345863975.pdfIn PDF document text
    • https://iphone-odklep.si/vsebina/vumetefaparisugozizosok.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/c2055cb7c516e8462d64c724ea48d672/38509991683.pdfIn PDF document text
    • https://www.audioclinica.pt/wp-content/plugins/super-forms/uploads/php/files/el8v2o22p9hrlqqo4ahtc5megs/83499269392.pdfIn PDF document text
    • https://ofly.om-digitalsolutions.cn/upload/files/35758552725.pdfIn PDF document text
    • https://lacgl.org/upload/editor/file/78894988561.pdfIn PDF document text
    • http://zamgph.com/uploads/file/0405550033.pdfIn PDF document text
    • https://299-45.com/CKEdit/upload/files/jizapefutuwakofuberaxazun.pdfIn PDF document text
    • https://esterkins.de/ckfinder/userfiles/files/lebobulujudalaj.pdfIn PDF document text
    • http://cuanhuaabshanquoc.vn/files/79086151221.pdfIn PDF document text
    • http://razzledazzleevents.in/userfiles/file/42613063314.pdfIn PDF document text
    • http://zentrumok.com/userfile/files/wajagixirurumedakow.pdfIn PDF document text
    • http://polimak.pl/userfiles/file/zawisojexosokojevumereba.pdfIn PDF document text
    • http://garage-ys.info/js/upload/files/36227721755.pdfIn PDF document text
    • http://valsadindustries.com/userfiles/file/45865367095.pdfIn PDF document text
    • http://rszm88.com/upfolder/e/files/20210918124153.pdfIn PDF document text
    • https://ktmcollege.org/public_html/userfiles/file/15579191961.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_off0000e612.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE612 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fe24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE24 18428 bytes
SHA-256: e181dfdcebb355f7592dfc80405425176b71b3076fe8d223195c6cdc7a6373b1
font_02_sfnt_off00012df4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DF4 10612 bytes
SHA-256: ad83d04d3be3065cb1bf7b60b2763f4965df9c44c1bc15a67c38b41a79e2180f