Malicious PDF — malware analysis report

Static analysis result for SHA-256 231f7468e6e16796…

MALICIOUS

PDF

74.5 KB Created: 2021-09-22 10:52:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 2ecfa8193c279ec7d227ea4a72a8323c SHA-1: 18c0e11c9aa1c8c231b7883d12c6a8ae64a0328d SHA-256: 231f7468e6e167966fddadda14348ac4f14cba565be2830d5146ad58a8c07cd2
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to various domains, many of which appear to be disposable hosting or compromised WordPress sites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' indicate a pattern of using link farms for malicious purposes. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://krisoc.ru/uplcv?utm_term=rope+hero+apk+download PDF link annotation
    • https://www.almuhja.com/ckfinder/userfiles/files/42241851257.pdfIn PDF document text
    • https://godahoian.com/app/webroot/upload/files/zanemopadefol.pdfIn PDF document text
    • https://zhongzing.com/uploads/files/202109182207086219.pdfIn PDF document text
    • http://xn--82cac8d3ajrc0gd0bo4a7nf3qg.com/userfiles/files/2159273619.pdfIn PDF document text
    • https://atlanticcompact.org/userfiles/files/pomixetutuvekedakepuk.pdfIn PDF document text
    • http://daiquangsico.com/img_duhoc/files/89882849172.pdfIn PDF document text
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/d95c9cf53b3d0e0ad70c4be3413c5929/meruzotelirewibiruxi.pdfIn PDF document text
    • https://rallstarawards.us/nbloom/fckuploads/file/fatiwifetulunoxurer.pdfIn PDF document text
    • http://frchem.cn/upload/files/didukizatamogafinefewevud.pdfIn PDF document text
    • http://cluboutletmoto.net/campannas/file/xejezizesejuxefumuja.pdfIn PDF document text
    • http://sanfrancescovet.com/userfiles/files/38218226577.pdfIn PDF document text
    • https://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/b89de50e105e8ed5d9df537b11f8df54/77841704130.pdfIn PDF document text
    • http://xatrbio.com/userfiles/file/bamakojoxinowogikasusazu.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16142e7c92005f---pezutegopu.pdfIn PDF document text
    • http://myucpb.net/userfiles/file/vekukitotiro.pdfIn PDF document text
    • https://weilaimachinery.com/userfiles/files/zuserutujemivajijarumunuz.pdfIn PDF document text
    • http://www.caslyn.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16131d9f61a849---mitosejafawalebodurelini.pdfIn PDF document text
    • https://digireg.li/upload/lazimoduj.pdfIn PDF document text
    • http://fobosgrunt.ru/files/ckfinder/files/23833450949.pdfIn PDF document text
    • https://dtd.com.pk/ckfinder/userfiles/files/28918096982.pdfIn PDF document text
    • http://illinoislivestock.org/userfiles/file/gusakuzunuxojuwefuroman.pdfIn PDF document text
    • http://netflor.pl/upload/File/kaxiso.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/161451754cc8c7---82694247322.pdfIn PDF document text
    • http://hongdacable.com/d/files/31738060906.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_off0000be6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE6E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d685.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD685 10356 bytes
SHA-256: 78bc0ec46a71313a62a72ed211ae38945d33287b8fc2126eaa5e764323f17139
font_02_sfnt_off0000ede0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDE0 18072 bytes
SHA-256: 3c534d456faf2d08fcc6d46804ab2933e6a23551f7071f65d7ce77c0dff8f3ae