Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c691066884fb324…

MALICIOUS

PDF

121.1 KB Created: 2021-08-21 10:51:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: eabe93230e7cb5cae8753ad19c7c1dcc SHA-1: 334c5bd85a08678b78874be93d2deda9bd89432a SHA-256: 5c691066884fb32480c9e81d76fb329eb5f57c2d1df49dbf485aee8f541062ce
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites acting as link farms. The ClamAV detection and ML classifier strongly indicate malicious intent, likely to lure users to malicious content or phishing sites. The presence of multiple links on disposable or compromised hosting suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 http://www.assignproject.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607524dab1340---66283917153.pdf In PDF document text
    • http://szentimresiklos.hu/upload/file/linipapalu.pdfIn PDF document text
    • http://teacherandtraining.com/coj_u/KK/userfiles/files/rajolomalevoz.pdfIn PDF document text
    • https://masterjobintl.com/ckfinder/userfiles/files/gakaninunuferutojifejav.pdfIn PDF document text
    • http://hagelkonzept.de/userfiles/file/vekunijejusedosudo.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1611a338f884d5---68118145316.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084a122b9a7e---96766301896.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a5bf722fbbc---84463092853.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/fslcdkvq6r9uq7tvhumjl9jj2o/65427506391.pdfIn PDF document text
    • https://jiptv.nl/wp-content/plugins/super-forms/uploads/php/files/vs4ibenh17rut0lb9pc31l40kc/fumowesunulezudure.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607987550dab8---biwoderudijivexiveg.pdfIn PDF document text
    • http://globalbando.com/DATA/upload/files/202106211458203918.pdfIn PDF document text
    • http://automotiveenergy.cz/userfiles/file/bikufozu.pdfIn PDF document text
    • https://brandonsmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/bq4g3bu8pulouimg8fc0ddfjl0/safiki.pdfIn PDF document text
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073c20d168da---5982118017.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160a4c005d39c8---27068656582.pdfIn PDF document text
    • http://lmleadmanagement.com/userfiles/files/76153702450.pdfIn PDF document text
    • http://autohondl.cz/userfiles/file/29379279292.pdfIn PDF document text
    • http://www.chatanakonci.cz/userfiles/file/12498638028.pdfIn PDF document text
    • http://jongauger.com/ckfinder/userfiles/files/liwotadimobe.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c1f04928ba---9221279933.pdfIn PDF document text
    • http://svsteinfurth.de/radsportfiles/file/rutotarujibodipulek.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160751ab1e6446---4345227078.pdfIn PDF document text
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/32cfead2b78b8292b6c3e6a673905a9c/43839009233.pdfIn PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160930b8ddcc09---divaxitelajujexukoniguno.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=ejercicios+prefijos+y+sufijos+5+primaria+pdfPDF 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_off00017377.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17377 18520 bytes
SHA-256: 4663450e09aae46cf539a355214890848ef9f29ad03b1491571421716dd19679
font_01_sfnt_off0001a2a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A2A4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001babb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1BABB 10996 bytes
SHA-256: 58b96b89b89d50bd9159ee4e41ae1e59747e5846a39dc42d16371f64bb46f225