Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb21e424dc09894c…

MALICIOUS

PDF

80.1 KB Created: 2021-08-26 14:33:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: bb1447892d0c178a96a51ac81b38c071 SHA-1: 174635fead49746915d0d2b88923e32b09fab4fb SHA-256: bb21e424dc09894c9d230cf3ee4e41bf5e7c9d52bf9d09b78701b621b78da1b0
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to compromised CMS upload storage and disposable hosting, suggesting it functions as a link farm to distribute further malicious content or phish users. The presence of these links and the overall structure strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

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://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076f4072eb35---4195421506.pdf In PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/t4ocoq8ur9jht1b7rn8ln8c93i/59302437891.pdfIn PDF document text
    • https://kaptenhoki.info/contents//files/31867378265.pdfIn PDF document text
    • http://washchienluoc.com/upload/file/belozukuzofaxefube.pdfIn PDF document text
    • https://vresponse.net/userfiles/file/84565806713.pdfIn PDF document text
    • https://exihomes.com/userfiles/files/45530968509.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160bc5238c3cc3---tidaxajunefimomobi.pdfIn PDF document text
    • http://mybed.tw/uploads//files/202108130724317724.pdfIn PDF document text
    • http://crystalnymph.by/wp-content/plugins/super-forms/uploads/php/files/a1781602e1d2f6a636b87ce026b567b0/gojel.pdfIn PDF document text
    • https://www.letspassdriving.co.uk/wp-content/plugins/super-forms/uploads/php/files/17t4tp88vofk7pailmggq1h71i/643501324.pdfIn PDF document text
    • http://xn--lv0az70cxar.tw/uploads/files/202108252259453913.pdfIn PDF document text
    • http://centrostudiapulia.it/files/files/62983563791.pdfIn PDF document text
    • https://salvamontbihor.ro/app/webroot/files/userfiles/files/98014555383.pdfIn PDF document text
    • https://atlastoursntravels.com/userfiles/file/81239427500.pdfIn PDF document text
    • http://mujuerp.com/uploads/ckeditor/files/20210608085753.pdfIn PDF document text
    • https://quickonboarding.com/wp-content/plugins/super-forms/uploads/php/files/e35ca426e85ea2980b3374fa8a3df07a/83302725077.pdfIn PDF document text
    • http://abakus-routing.co.uk/ckfinder/userfiles/files/kaxokuw.pdfIn PDF document text
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/bd9b4f4cd3a4be2767e3c5e2679c9b4b/dozudorizigini.pdfIn PDF document text
    • http://johndanton.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/30722200066.pdfIn PDF document text
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/e8743dd1ab890efec974cd30c052eb80/wufedivoxefanozufimoram.pdfIn PDF document text
    • http://jcon-aps.dk/userfiles/file/joxexanolanepowalo.pdfIn PDF document text
    • https://gastrotest.co/ckfinder/userfiles/files/jizigevezidab.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/160a7f501f34f4---47395913096.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a49c1945af1---lanitaxanosikavewawimubav.pdfIn PDF document text
    • http://lamelove-zakryti.cz/userfiles/file/xirovobalojefexu.pdfIn PDF document text
    • https://hssipm.com/wp-content/plugins/super-forms/uploads/php/files/269d4a37bef7dbff18b592064361a1dd/judipozomijifatog.pdfIn PDF document text
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/tmp/30247238951.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=off+the+subjectPDF 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_off0000d7de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7DE 16548 bytes
SHA-256: dc63d263d786dd07b696d33b4d719891904680ca07fe7d0e2e72328e7afb5c1a
font_01_sfnt_off000102a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102A5 10204 bytes
SHA-256: d3cbce56d42c29818e2e6da133cd215108884d5c87cc556f253ea69b98a58d42
font_02_sfnt_off000119c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119C4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1