Malicious PDF — malware analysis report

Static analysis result for SHA-256 191b7499b3a812a8…

MALICIOUS

PDF

112.3 KB Created: 2021-09-01 08:17:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 777fa47bc0ae1fd060ba244133776257 SHA-1: a457f3ad9ba62dc78883056f37fbd8b4916232bf SHA-256: 191b7499b3a812a850d7b1c418a26a30dfc93efa5430d71f694196abffc9aada
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6305

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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://laborke.ru/uplcv?utm_term=earthquakes+and+volcanoes+study+guide PDF link annotation
    • https://mariapolis.net/ckfinder/userfiles/files/41537557965.pdfIn PDF document text
    • https://oncallanatomist.org/ckfinder/userfiles/files/3874873052.pdfIn PDF document text
    • https://www.nestroots.com/wp-content/plugins/super-forms/uploads/php/files/4nm9cu1osg8cl0su00umtajq01/tijipinid.pdfIn PDF document text
    • https://www.okcfarmersmarket.com/wp-content/plugins/super-forms/uploads/php/files/756e190be0d9094a21871b4e996c3c54/wakowasumefuzux.pdfIn PDF document text
    • http://gildiamasterov.ru/userfiles/file/fasixamatezivoxetuduwilib.pdfIn PDF document text
    • http://ahcxdq.com/uploads/file/170544296310.pdfIn PDF document text
    • http://dogoxuavanay.vn/uploads/files/savevabijikanazurazud.pdfIn PDF document text
    • https://www.profiemg.cz/upload/ck/files/44261037466.pdfIn PDF document text
    • http://hyundai-dongdo.vn/images/files/82055748187.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/ar9dpr8i1dvhcov1lk6n6ilrc5/94176744080.pdfIn PDF document text
    • http://joy05.com/_UploadFile/Images/file/nobemabis.pdfIn PDF document text
    • http://marty-triple-m.ch/inhalt/files/98335322429.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aea6a963cc9---97766212154.pdfIn PDF document text
    • http://gerocuki.hu/user/file/kizefurakedifexofutewu.pdfIn PDF document text
    • http://sspvjd.com/FileData/ckfinder/files/20210808_25F1013573741EAA.pdfIn PDF document text
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/efri9osduje3dt06ltv8kdaipd/79415047210.pdfIn PDF document text
    • https://holcom-solar.com/webroot/img/files/95965384612.pdfIn PDF document text
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7ce48ef565---78706132368.pdfIn PDF document text
    • https://avayemehr-carpet.ir/data/file/nepugegofuzaxevibu.pdfIn PDF document text
    • http://designpavelzapletal.cz/files/file/taziba.pdfIn PDF document text
    • http://touristclub.in/userfiles/file/30965151306.pdfIn PDF document text
    • http://fincasotilloviejo.es/files/sotillo/_repo/file/20650782345.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/00254463cfe0b0e882f26f671e21ff2d/61583272112.pdfIn PDF document text
    • https://mimpishio1bet.net/contents//files/nisukujijoji.pdfIn PDF document text
    • http://gldbirdgel.com/user_img/files/gegaz.pdfIn 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_off00015a3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15A3B 11148 bytes
SHA-256: cd510c91fac67971d24fd7507147051e7f0ae0ab480c7bc9327a7a377d57cb0c
font_01_sfnt_off000173cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x173CB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00018bdd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18BDD 18948 bytes
SHA-256: f01d07ef28832fee7bb476322ace20c9cbf1c715cc16e0cdf5ebdb0bededfe33