Malicious PDF — malware analysis report

Static analysis result for SHA-256 868d3a80720f3bb1…

MALICIOUS

PDF

73.8 KB Created: 2021-09-23 21:54:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 9c7fe9223664ccf1ec91b6fa5aa936eb SHA-1: 17e2643a28c35c37ea6d8865a0a07bbf24f0a23e SHA-256: 868d3a80720f3bb11dbab8b79375af10e5bc79d6f831eac7e96525f0e1db0b51
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs, several of which point to compromised WordPress uploads or disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond what the heuristics reveal.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • 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.
  • 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.sczct.com/up_files/file/tilobetinavefabarodadofej.pdf In PDF document text
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fcc67a4dbe---1147566941.pdfIn PDF document text
    • http://hla.vn/upload/files/92083592361.pdfIn PDF document text
    • https://protectname.xyz/whoisprivacy/userfiles/files/79388610630.pdfIn PDF document text
    • http://suachuadienlanhhoaphat.com/hinhanh_fckeditor/file/53617044513.pdfIn PDF document text
    • https://majubesar.net/contents/files/29237547205.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16140385395101---monobatemidafuno.pdfIn PDF document text
    • https://nikunjfoundation.org/ckfinder/userfiles/files/91098053454.pdfIn PDF document text
    • http://dolphinegypt.net/userfiles/file/liduxafavopagobosexup.pdfIn PDF document text
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/847a9124e7414cea7b69c00e2c05d6be/15341160635.pdfIn PDF document text
    • http://www.corazondelsol.es/ckfinder/userfiles/files/96906345751.pdfIn PDF document text
    • https://equinox-e.com/upload/UserFiles/file/minukasonafevo.pdfIn PDF document text
    • http://devitohomesorlando.com/userfiles/files/60027862976.pdfIn PDF document text
    • https://mmrh.myagenda.cz/pictures/editor/files/jelupopunej.pdfIn PDF document text
    • https://congchunghadong.com/uploads/files/41815156351.pdfIn PDF document text
    • https://zhansq.cn/upload/file/karumusizibovemepupiniku.pdfIn PDF document text
    • http://avtokapriz42.ru/userfiles/file/noxave.pdfIn PDF document text
    • http://www.parinet.fi/tiedostot/files/61986747061.pdfIn PDF document text
    • http://gyogytornasz.hu/editor_up/16719901321.pdfIn PDF document text
    • https://brincandoeaprendendo.com/fotosempresa/files/14316120044.pdfIn PDF document text
    • http://haciogullari.com/depo/sayfaresim/file/20733782971.pdfIn PDF document text
    • https://villanakarin.com/userfiles/files/17442305271.pdfIn PDF document text
    • http://anhuizpyy.com/upload_fck/file/2021-9-23/20210923060716233908.pdfIn PDF document text
    • http://thegioimercedes.com/upload/files/83001231560.pdfIn PDF document text
    • https://dacinsara.ro/fckfiles/file/masapalewerusag.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=police+truck+robot+gamePDF 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_off0000be8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE8E 10636 bytes
SHA-256: d31e97a0241b05f240329c06e1147138ac042e5a4316d4d1490565e7e3ee46a0
font_01_sfnt_off0000d6f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6F4 16492 bytes
SHA-256: 348de6acde6ce5c083060706547c532654155ec5e0714396306ab4a5dbd70a2f
font_02_sfnt_off0001017d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1017D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1