Malicious PDF — malware analysis report

Static analysis result for SHA-256 31077452c95a905b…

MALICIOUS

PDF

76.9 KB Created: 2021-09-17 08:26:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: aba3e9f0d277524165ab8de21278534a SHA-1: cd2fcacd0a81ab59a513473b288d35126ea32faf SHA-256: 31077452c95a905b63e96409eb1b355e16725bfd37c34ab5a59e1ce1d6ae4e1c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users to malicious content. The presence of these link farms and the overall detection as a phishing trojan strongly suggest an attempt to lure users to external sites for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 https://huntic.ru/uplcv?utm_term=use+android+camera+as+webcam+usb PDF link annotation
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141571314ede---kexixawukozejikitofiweni.pdfIn PDF document text
    • http://vps73.juicy-group.com/editor_upload_image/file/rotuvovipig.pdfIn PDF document text
    • http://strojsteel.cz/webpagebuilder/ckfinder/userfiles/files/dokowofazomovasot.pdfIn PDF document text
    • https://santehsevast.ru/userfiles/files/46355768131.pdfIn PDF document text
    • http://sd-admin.fazendapenaazul.com/ckeditor/uploads/files/vuxonomojeb.pdfIn PDF document text
    • https://lescourailleurs.com/upload/editor/file/supazimamatorutofavegax.pdfIn PDF document text
    • http://ncdesign.it/userfiles/files/tefusopenenibamesab.pdfIn PDF document text
    • http://georgewongdesign.com/gwd/upload/files/76106424961.pdfIn PDF document text
    • http://monarchiaerembolt.hu/tmp/51169738798.pdfIn PDF document text
    • http://fszhenjia.com/upfolder/e/files/20210901153507.pdfIn PDF document text
    • http://didopack.com/files/50154576203.pdfIn PDF document text
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/161367e19f00c0---posatogarifegura.pdfIn PDF document text
    • https://beaszemin.com/files/25160643717.pdfIn PDF document text
    • http://expertsystemgroup.com/file_media/file_image/file/titebumusolonirefikutus.pdfIn PDF document text
    • https://chiuman-hk.com/images/file/9537827488.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/16140ca585b040---xepanoderenedarefi.pdfIn PDF document text
    • http://tomboy2.com/images/library/File/89021334434.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16131ff061028e---27804127447.pdfIn PDF document text
    • http://gyndoktors.de/ckfinder/userfiles/files/61758488940.pdfIn PDF document text
    • https://brillimet.com/uploads/files/202109011651451651.pdfIn PDF document text
    • http://eco-building.cz/UserFiles/File/14803644455.pdfIn PDF document text
    • http://rtm-plus.com/ckfinder/userfiles/files/45944767928.pdfIn PDF document text
    • http://back2wood.de/userfiles/file/wusatuxujuwederubomiwor.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/161406a643e9fc---36246070763.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_off0000c449.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC449 10720 bytes
SHA-256: 860eccaf902f2ce666fb8359769c36db1543a280d20a203a6a75bfbefc617f05
font_01_sfnt_off0000dcf4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCF4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f506.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF506 18812 bytes
SHA-256: dcfad31fb9c33fce471e7484f0562139323f43309e816e17279bdb1e8fd27ee2