Malicious PDF — malware analysis report

Static analysis result for SHA-256 169f1e5fbd73b8f5…

MALICIOUS

PDF

91.6 KB Created: 2021-08-23 14:33:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: a5283c27bbdbbcccfd6f6a136fa7087f SHA-1: 7dc223100866cdc41672f173c4ce770a7dab1cdb SHA-256: 169f1e5fbd73b8f52e6f7017bdabf04e2db40f16ee252f99c376d915b9310af4
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to multiple distinct hosts, some of which appear to be compromised WordPress upload directories. The embedded URLs suggest an attempt to direct users to external malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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://bekkercoon.ru/ckfinder/userfiles/files/fatamojivaboti.pdf In PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071c50842486---14125459131.pdfIn PDF document text
    • http://skrabl.pl/www/rpbd/fck/file/12400305742.pdfIn PDF document text
    • https://nyirfa.hu/uploads/files/bibumovofevaguzosemotuto.pdfIn PDF document text
    • https://xn--80aaijzh9b.xn--90ae/documents/file/96519365418.pdfIn PDF document text
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082fdc84d23c---lazibarivepewofebimove.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/ab046f0f328013febcc00492262ce660/56674712583.pdfIn PDF document text
    • http://medica-brno.com/files/13026157062.pdfIn PDF document text
    • https://fablab808.com/nbloom/fckuploads/file/sonaj.pdfIn PDF document text
    • http://ridendo.cz/files/file/52667316713.pdfIn PDF document text
    • http://eko-inwest.eu/upload/file/roluvatukoru.pdfIn PDF document text
    • https://autotoner123.com/home/autotone/public_html/ckeditortest_WORKING/ckfinder/userfiles/files/varojejifuxopinobajola.pdfIn PDF document text
    • http://macautemple.com/userfiles/file/61520762420.pdfIn PDF document text
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/f353de7cc12c8bee2283319ac9453cdf/7852916479.pdfIn PDF document text
    • https://www.corpeverest.com/ckfinder/userfiles/files/9815914917.pdfIn PDF document text
    • https://archcosmeticstudio.com.au/wp-content/plugins/super-forms/uploads/php/files/b03f31f28f8598d04220f59b2f9084ef/romewiwisoko.pdfIn PDF document text
    • http://clinivetmadonnadirosa.eu/userfiles/files/74490115849.pdfIn PDF document text
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/1607721df05c4a---nipavofarefebewube.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b29b4ae6ea8---79911898002.pdfIn PDF document text
    • http://highlandhighclassof1962.com/clients/c/c3/c330a44b04b080977bf299ea430a317d/File/37415437597.pdfIn PDF document text
    • http://romangruszecki.com/uploaded/file/38136259758.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4e3ac5363b---rewenosotem.pdfIn PDF document text
    • https://urbanshapes.in/userfiles/file/74722335794.pdfIn PDF document text
    • http://ifa-astrologie.de/userfiles/file/83380213401.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=calculus+ab+section+1+part+a+answersPDF 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_off0000f902.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF902 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011114.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11114 20732 bytes
SHA-256: ab2108dc2b45cf1078fb1a17e456425361770affca5851216925367cc7a52652
font_02_sfnt_off00014699.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14699 10776 bytes
SHA-256: ab8656cd8fcd6d24433d76f705c9cf02931608f36f581333d3a42e41c1974d87