Malicious PDF — malware analysis report

Static analysis result for SHA-256 26df99361e1610da…

MALICIOUS

PDF

70.9 KB Created: 2021-09-15 14:04:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: a4c669809ab5318c53c68fbd92841a58 SHA-1: d7a1655c74e7fd8cb0d8bfb7bb022ed3332e92c2 SHA-256: 26df99361e1610da12b5450640a2e5d478acc4ddb15bbd76a77e33b2c30faf5c
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs, many pointing to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of multiple external URIs and link farms suggests an attempt to direct users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://portalcom-b2b.es/img/user//file/_0949513001631520808.pdf In PDF document text
    • https://mongolia-volkslift.com/uploads/files/12604042355.pdfIn PDF document text
    • https://abisspaandboutique.com/nbloom/fckuploads/file/53103229108.pdfIn PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135bb1a06fce---tavirulabugo.pdfIn PDF document text
    • http://spbi.cz/res/file/63788334623.pdfIn PDF document text
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1613f39b50b5f8---rakifizaxem.pdfIn PDF document text
    • http://zhizhencn.com/filespath/files/20210907184521.pdfIn PDF document text
    • https://reparationmobile.net/userfiles/file/zujejiwajofasexasule.pdfIn PDF document text
    • http://lemma-studio.pl/userfiles/file/56168287630.pdfIn PDF document text
    • http://cansuyu.org/resimler/files/60690537820.pdfIn PDF document text
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1613a35845c91e---dekujunesegexesadanexi.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/c0e60e429u7ig545drdbid99k6/68502136508.pdfIn PDF document text
    • http://architects-desk.com/uploadsfile/92701687709.pdfIn PDF document text
    • http://studiotecnicoforace.eu/userfiles/files/butadewaxinajum.pdfIn PDF document text
    • http://3dtechgroup.com/uploads/image/files/26318562586.pdfIn PDF document text
    • http://rm-centr.ru/uploads/file/kusexibikuzekowuxad.pdfIn PDF document text
    • http://study4student.com/cache/fck_files/file/jativojiforuzixumowi.pdfIn PDF document text
    • http://onnetsolution.in/userfiles/file/88955014515.pdfIn PDF document text
    • http://koutingchina.com/upload/files/52854739266.pdfIn PDF document text
    • https://www.xyoaa.org/sites/default/files/files/fubakasotadovolegapuju.pdfIn PDF document text
    • http://fatfailogistics.com/fckeditor/files/file/terasa.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613bfcb3594d7---sejegiwopojagos.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=lion+vpn+freePDF 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_off0000b7f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7F5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d00b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD00B 9900 bytes
SHA-256: 9e6172f9e6f48cbdba80b133b43b46145ff6e8c95c5bfe8e257b1c236202dff3
font_02_sfnt_off0000e5f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5F3 16044 bytes
SHA-256: 2345ca7781fde92e26b2829d8d8d18be48602f365d15f991441ee560b5fe1dcf