Malicious PDF — malware analysis report

Static analysis result for SHA-256 5538679dd56c77ed…

MALICIOUS

PDF

72.8 KB Created: 2021-09-29 14:15:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 7fd299ee6bc905ab6d2c463eee99b8d4 SHA-1: 05ebfe94584a13b03f3c6381461e07f1fa120437 SHA-256: 5538679dd56c77ed96337a630c6e5c8113fdb53f82100807ef64cc3c2b6bec75
156 Risk Score

Malware Insights

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

The PDF file 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, with several URLs pointing to compromised CMS upload storage, suggesting an attempt to redirect users to malicious content. The presence of numerous embedded URLs, including one hosted on a compromised WordPress site, strongly indicates a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://carrollcountylawyers.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/13690326207.pdf In PDF document text
    • http://farmina.ru/uploads/files/62737524584.pdfIn PDF document text
    • http://pegastelco.com/pictures/files/sutobopikexejosibe.pdfIn PDF document text
    • http://yuli-china.ru/d/files/buroxozalomegiliwe.pdfIn PDF document text
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/1740c8e46a387067588dc840ff0fab35/90816149949.pdfIn PDF document text
    • https://acp-luxusingatlanok.hu/ckfinder/userfiles/files/zibituti.pdfIn PDF document text
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/cdb9e320c30882c5794424d96653a5fd/13396970470.pdfIn PDF document text
    • http://collegium-connect.nl/ckupload/files/79288970655.pdfIn PDF document text
    • http://dui-antidote.com/images/userfiles/file/mivefujopazowuwason.pdfIn PDF document text
    • http://ctyrkolky-gamax.cz/data/dokumenty/tefiminufogeji.pdfIn PDF document text
    • http://dd-eng.com/files/files/21073963802.pdfIn PDF document text
    • http://m2m2design.com/userfiles/66696557256.pdfIn PDF document text
    • http://fitnessklub-impuls.pl/uploads/assets/file/wuzujedatifalijadu.pdfIn PDF document text
    • https://sandp-engineering.com/ckfinder/userfiles/files/rojapumodixezujinulofasod.pdfIn PDF document text
    • http://isleford.com/filespath/files/20210917050024.pdfIn PDF document text
    • http://esistore.de/userfiles/file/kawolatiguxuvunuzadup.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16140767b2236a---8306487071.pdfIn PDF document text
    • http://yangs-ns.com/ckfinder/userfiles/files/20210924081817.pdfIn PDF document text
    • http://bigdoughpizza.com/uploads/files/90279132331.pdfIn PDF document text
    • http://tangiahoang.com/skinkorea/Images_upload/files/vekaninupojeximit.pdfIn PDF document text
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614ba52fd82d3---wefegokufetog.pdfIn PDF document text
    • http://inkjetartandimage.com/Uploads/file/tomodudipumimapexuwuk.pdfIn PDF document text
    • http://anpo.vn/upload/files/32327202683.pdfIn PDF document text
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/161543ba5288d3---mezizupifejaxujixode.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=how+can+i+read+telegram+messages+without+seenPDF 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_off0000b6ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6CE 17488 bytes
SHA-256: 33c3638031bc0fe97254580cf994d131261e436d3b9d5be48c1a6c23bd35fafe
font_01_sfnt_off0000e3b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3B2 10992 bytes
SHA-256: 77cf22dd6c4226288817fe2d0c52dc20012438b12eff7b1aeccdd18906f11855
font_02_sfnt_off0000fcda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCDA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1