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Nariyoshi Chida/千田 忠賢, PhD

nariyoshichidamm AT gmail DOT com
Last updated on October 20, 2026

Professional Experience

Apr. 2025 - Present Distinguished Researcher at NTT Social Informatics Laboratories
Apr. 2024 - Mar. 2025 Associate Distinguished Researcher at NTT Social Informatics Laboratories
Apr. 2023 - Mar. 2024 Researcher at NTT Social Informatics Laboratories
Apr. 2022 - Mar. 2023 Researcher at NTT Security Japan (Temporary transfer from NTT Social Informatics Laboratories)
Jul. 2021 - Apr. 2022 Researcher at NTT Social Informatics Laboratories
Apr. 2017 - Jul. 2021 Researcher at NTT Secure Platform Laboratories

Publications

Refereed Journal Publications

  1. Nariyoshi Chida, Daisuke Yamaguchi, and Hiroyuki Uekawa
    "Towards More Accurate DOM-based XSS Detections for Real-World String Manipulations" (Recommended Paper, in Japanese)
    IPSJ Journal, Vol. 66, No. 10, pp. 1399-1408
    October 15, 2025
  2. Nariyoshi Chida and Tachio Terauchi
    "On Lookaheads in Regular Expressions with Backreferences" (Extended Version)
    IEICE Transactions on Information and Systems E106-D (5), pp. 959-975,
    2023
  3. Nariyoshi Chida, Yo Kanemoto, Kazufumi Aoki, and Jun Miyoshi
    "A Formal Grammar-based Approach Toward Attack Scenario Reconstruction" (Recommended Paper, in Japanese)
    IPSJ Journal, Vol. 61, No. 2, pp. 500-509,
    February 15, 2020
  4. Nariyoshi Chida and Kimio Kuramitsu
    "Parsing Expression Grammars with Unordered Choices"
    Journal of Information Processing, Vol. 25, pp. 975-982,
    December 2017

Refereed Conference Publications

  1. Nariyoshi Chida and Tachio Terauchi
    "Repairing Regex-Dependent String-Manipulation Programs",
    The 38th International Conference on Computer Aided Verification (CAV 2026), Lisbon, Portugal
    July 26-29, 2026 [pdf]
  2. Daisuke Yamaguchi, Shinobu Saito, Takuya Iwatsuka, Nariyoshi Chida, and Tachio Terauchi
    "A Secure Mocking Approach towards Software Supply Chain Security",
    The 40th IEEE/ACM International Conference on Automated Software Engineering, New Ideas and Emerging Results Track (ASE-NIER 2025), Seoul, South Korea
    November 16-20, 2025
  3. Nariyoshi Chida, Daisuke Yamaguchi, and Hiroyuki Uekawa
    "Short Paper: Speeding Up Pre-Image Computation of Regular Languages under Prioritized Streaming String Transducers for Injection Vulnerability Detection",
    The 20th Workshop on Programming Languages and Analysis for Security (PLAS 2025), Taipei, Taiwan
    October 13, 2025
  4. Nariyoshi Chida and Tachio Terauchi
    "Repairing Regex-Dependent String Functions",
    The 39th IEEE/ACM International Conference on Automated Software Engineering (ASE 2024), Sacramento, California, United States
    October 27-November 1, 2024 [pdf]
  5. Nariyoshi Chida and Tachio Terauchi
    "Repairing Regular Expressions for Extraction",
    The 44th ACM SIGPLAN Conference on Programming Language Design and Implementation (PLDI 2023), Orlando, Florida, United States
    June 17-21, 2023 [pdf, video]
  6. Nariyoshi Chida and Tachio Terauchi
    "On Lookaheads in Regular Expressions with Backreferences",
    The 7th International Conference on Formal Structures for Computation and Deduction (FSCD 2022), Haifa, Israel
    August 2-5, 2022 [pdf, slides]
  7. Nariyoshi Chida and Tachio Terauchi
    "Repairing DoS Vulnerability of Real-World Regexes",
    The 43rd IEEE Symposium on Security and Privacy (S&P 2022), San Francisco, California, United States
    May 22-26, 2022 [pdf, experimental data, video]
  8. Nariyoshi Chida, Yuhei Kawakoya, Dai Ikarashi, Kenji Takahashi, and Koushik Sen
    "Is Stateful Packrat Parsing Really Linear in Practice? -- A Counter-Example, an Improved Grammar, and Its Parsing Algorithms",
    The 29th ACM SIGPLAN International Conference on Compiler Construction (CC 2020), San Diego, California, United States
    February 22-26, 2020 [pdf (Full version), experimental data]
  9. Nariyoshi Chida and Kimio Kuramitsu
    "Linear Parsing Expression Grammars",
    The 11th International Conference on Language and Automata Theory and Applications (LATA 2017), Umeå, Sweden
    March 6-9, 2017 [pdf, slides]

Presentations

  1. Nariyoshi Chida and Tachio Terauchi
    "Repairing Regex-Dependent String Functions",
    The 27th Workshop on Programming and Programming Languages (PPL 2025), March 2025
  2. Nariyoshi Chida and Tachio Terauchi
    "Repairing Regular Expressions for Extraction",
    The 26th Workshop on Programming and Programming Languages (PPL 2024), March 2024
  3. Nariyoshi Chida and Tachio Terauchi
    "On Lookaheads in Regular Expressions with Backreferences",
    The 25th Workshop on Programming and Programming Languages (PPL 2023), March 2023
  4. Nariyoshi Chida and Tachio Terauchi
    "Repairing DoS Vulnerability of Real-World Regexes",
    The 24th Workshop on Programming and Programming Languages (PPL 2022), March 2022
  5. Nariyoshi Chida, Yo Kanemoto, Kazufumi Aoki, and Jun Miyoshi
    "A Formal Grammar-based Approach Toward Attack Scenario Reconstruction" (CSS2018 Incentive Award; in Japanese)
    Computer Security Symposium 2018 (CSS 2018), October 2018
  6. Nariyoshi Chida and Kimio Kuramitsu
    "Generalized Parsing Expression Grammars" (in Japanese)
    The 113th Meeting of the IPSJ SIG on Programming (PRO113, PRO-2016-5), March 2017 [slides]
  7. Nariyoshi Chida and Kimio Kuramitsu
    "A Partial Conversion of Parsing Expression Grammars to Deterministic Finite Automata" (poster presentation),
    The 14th Asian Symposium on Programming Languages and Systems (APLAS 2016), Hanoi, Vietnam
    November 21-23, 2016 [poster]
  8. Nariyoshi Chida and Kimio Kuramitsu
    "Regularity of Linear Parsing Expression Grammars" (in Japanese)
    The 111th Meeting of the IPSJ SIG on Programming (PRO111, PRO-2016-3), October 2016
  9. Nariyoshi Chida and Kimio Kuramitsu
    "The Implementation of an Automata-Based Matching Algorithm for Regular Expressions with Lookaheads" (poster presentation)
    The 18th Workshop on Programming and Programming Languages (PPL 2016), March 2016 [poster]
  10. Nariyoshi Chida, Masanori Sato, and Kimio Kuramitsu
    "Judgement of Converting Parsing Expression Grammar into Deterministic Finite Automaton"
    The 106th Meeting of the IPSJ SIG on Programming (PRO106, PRO-2015-3), November 2015

Invited Talks

  1. Nariyoshi Chida
    "Repairing Regex-Dependent String Functions",
    IPSJ/SIGSE Software Engineering Symposium (SES 2025) (Invited Talk), September 2025
  2. Nariyoshi Chida
    "Repairing Regex-Dependent String Functions",
    The 24th Forum on Information Technology (FIT 2025) (Top-Conference Special Talk), September 2025
  3. Nariyoshi Chida
    "On Regular Expressions and the Extensions"/"Repairing Regular Expressions from Examples"
    PPL Summer School 2023 (Invited Talk), September 2023
  4. Nariyoshi Chida and Tachio Terauchi
    "Repairing DoS Vulnerability of Real-World Regexes",
    The 22nd Forum on Information Technology (FIT 2023) (Top-Conference Special Talk), September 2023
  5. Nariyoshi Chida and Tachio Terauchi
    "Repairing DoS Vulnerability of Real-World Regexes",
    Workshop on Cryptography and Information Security 2022 (WCIS 2022) (Invited Talk), September 2022
  6. Nariyoshi Chida, Yuhei Kawakoya, Dai Ikarashi, Kenji Takahashi, and Koushik Sen
    "Is Stateful Packrat Parsing Really Linear in Practice? — A Counter-Example, An Improved Grammar and Its Parsing Algorithms —"
    The 37th JSSST Annual Conference (Top-Conference Special Talk), September 2020 [video]

Awards

Professional Services

Projects

Current

Past

CVEs

  1. CVE-2026-61556: An infinite loop vulnerability in LiquidJS.
  2. CVE-2022-25887: A regular expression denial of service (ReDoS) vulnerability in sanitize-html.
  3. CVE-2021-33503: A regular expression denial of service (ReDoS) vulnerability in urllib3.